Next week’s elections will not only determine the balance of power on Capitol Hill but also will seal the fate of the Trump administration’s legislative agenda for the next two years and set the landscape of the 2020 presidential campaigns.

The direction of the nation’s most contentious and consequential issues — health care, immigration, taxes, climate change, trade, gun control, ethics and campaign finance overhauls and oversight of the administration — hinges on what voters decide Nov. 6.

The stakes are enormous.

If Democrats capture control of just one chamber of Congress, most likely the House, they can deny President Donald Trump and their GOP colleagues their legislative wish list, slamming shut the window for a new round of tax cuts or divisive changes to entitlement programs. With the subpoena power that comes with a committee gavel, House Democrats will kick-start Congress’ largely dormant oversight role, probing everything from the president’s hidden personal tax returns to the administration’s handling of health care and financial regulations, as well as its response to hurricanes, the Russian election interference investigation and other international crises.

With control of the House, Democrats could push along legislation on pivotal matters, such as rescuing or expanding parts of the 2010 health care law, raising the federal minimum wage and addressing gun control, ethics in government and political money issues. Those bills wouldn’t likely make their way into law even if the party wins control of the Senate — the president has veto power after all. But it would allow Democrats to lay out an alternative policy vision, incubating proposals that the party’s 2020 White House hopefuls could embrace, or reject.

“In many ways, the House Democrats are going to determine in those first 100 days what the common platform of the 2020 presidential candidates will be,” said Rep. Ro Khanna, a California Democrat and member of the Congressional Progressive Caucus. “What we pass on the House side, even if it doesn’t become law, will become the mantra of the presidential candidates.”

It won’t be all harmony within the Democratic caucus. The party will need to resolve its leadership lineup and will contend with an emboldened progressive wing at the same time it needs to show voters proof that it can once again govern.

Though less likely than taking the House, Democrats taking the Senate in the 116th Congress could intensify pressure on the executive branch through oversight investigations and efforts to block administration goals — think border wall, for example — through the appropriations process.

Most importantly, they could hold up or even block Trump’s judicial and executive branch nominees.

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On the flip side, if Republicans maintain control of Congress, the election results would serve as an endorsement of the Trump-GOP agenda and embolden the party to carry on with more tax cuts and conservative appointees, changes to welfare programs and a hard-line approach to immigration and border enforcement.

In a Democrat-controlled House or Senate, the biggest concern for Republicans on the Hill and their conservative allies outside Congress isn’t that the other party will wield the power over the next two years to enact progressive or any other kind of major legislation. Instead it’s about the potential for dashed hopes, lost opportunities and the end of what many conservatives felt should have been the midpoint, not the end, of a stretch of policy victories, including more tax cuts and regulatory overhauls.

“We didn’t accomplish as much as we wanted to in these first two years,” said Tim Chapman, executive director of the conservative Heritage Action for America, the lobbying arm of The Heritage Foundation. “We didn’t get where we wanted to on fixing the health care system or welfare reform. … You don’t know that you’re going to get that window again in 2020.”

With either chamber of Congress in Democratic hands, Republicans will face other fears: that Trump could morph into more of a liberal on signature issues such as funding infrastructure projects, possibly flipping on their policy priorities to start cobbling together deals with Democratic leaders. Congressional Republicans could also lose the already flighty focus of their president who, when it comes to trade policy, often sounds more like the Elizabeth Warren wing of the Democratic Party than any faction of the GOP.

Still, one of the biggest questions, if Democrats hold the power in either chamber, remains: Can they work with a president whom their voters despise, especially when it’s the left’s angry and motivated base that will have helped catapult the party back into power?

“The president is tacking towards the center in everything but his rhetoric,” said John Feehery, a former congressional Republican leadership aide, who is now a partner at the lobbying shop EFB Advocacy. “Democrats are tacking further to the left because they don’t like his rhetoric.”

Trading places

The new free-trade deal with Mexico and Canada, a renegotiation of the 1994 North American Free Trade Agreement, includes tougher protections for workers, something Democrats have called for. “There’s a lot in there that Democrats should like,” Feehery said. “But do they want to give the president a victory?”

Celeste Drake, trade policy specialist with the AFL-CIO, said congressional Democrats are “still coalescing” when it comes to the new deal, which would require Congress’ approval. Trade, of course, is an issue that splits the party’s few free-traders with the majority of the caucus, which is largely skeptical of the impact of big trade deals on jobs and workers’ pay. Drake said the new deal’s stronger labor provisions sound appealing but isn’t sure how they’d be enforced.

The president’s language about the new agreement also leaves Democrats uncomfortable. “His rhetoric on NAFTA has been very xenophobic,” she said. “How does that square with the Democrats who have long been calling for a NAFTA reform? … Democrats will be looking to put a stamp on this and to address those issues.”

Democrats, in power in either the House or the Senate, will also look to put their stamp on health care and prescription drug matters. If voters often accuse politicians of flip-flopping on a policy, lawmakers have seen much of the electorate do an about-face on the 2010 health care law, which cost Democrats their House majority in that year’s elections. Now quite the opposite has popped up on the campaign trail. Instead of vilifying lawmakers for the law, a majority of voters in some of the country’s tightest electoral contests want to preserve at least its protections for patients with pre-existing conditions.

Sen. Amy Klobuchar, a Minnesota Democrat who is up for re-election this year, said keeping in place those protections as well as measures to bring down pharmaceutical prices have become huge rallying points on the campaign trail, in Democrats’ favor.

On the pharmaceutical prices, she said, “I’m excited about that because I’m the lead on a bunch of those bills” and the discussion of those matters on the campaign trail “will really help to finally propel that issue into next year.” Trump has also signaled his interest in reining in drug prices.

Immigration, however, offers a stark contrast between the two parties and between congressional Democrats and the president. “I’m hoping we win all these seats, and that will be a big pushback on some of the rhetoric there, and maybe we can then move on comprehensive reform,” Klobuchar adds.

Republicans have also worked to differentiate themselves from Democrats on style and rhetoric, not just policy. The GOP is stoking fears about unruly mobs of leftists taking over Washington.

“We got a little preview of what life would be like here in the United States Capitol with Democrats in charge, if they’re successful in capturing one or both houses of the Congress after the midterm elections: angry mobs, intimidation, showing up at people’s homes, mailing them coat hangers, and trying to intimidate members,” Senate Majority Whip John Cornyn of Texas told reporters in the Capitol after the debate over Supreme Court Justice Brett M. Kavanaugh.

“That’s not exactly my ideal of how the United States Congress should operate.”

The debate over civility has taken a scary turn in recent days with suspected explosive devices turning up in the mail to several prominent Democrats including some sitting lawmakers.

Top of the agenda

In the House, if Democrats control the chamber, a vocal group of incumbents, including House Minority Whip Steny H. Hoyer of Maryland, along with some of the likely stars of the incoming freshman class, have called for the new majority’s top priority and first order of legislative business to be a far-reaching overhaul of the nation’s campaign finance, voting rights, lobbying and ethics laws.

“All of these items should be packaged, in my opinion, into one reform bill and addressed in the opening days of the next Congress,” Hoyer said recently. “Democrats, if entrusted with the leadership will do exactly that. … If Democrats can fix government we can earn the trust of voters to lead on addressing health care, infrastructure, jobs, the environment and so many other critical issues.”

Hoyer’s endorsement of such a measure is significant. It’s the kind of talking point one would expect from Vermont independent Sen. Bernie Sanders, not Hoyer, who enjoys a friendly rapport with the nation’s business community and has a long list of former aides in the K Street lobbying corridor.

A major campaign finance, lobbying, ethics and anti-corruption package would not pass the Senate, but the proposal would allow Democrats to deliver, in the House, a platform for the party, including those running for president in 2020.

“We’ll be creating a new baseline of what Democrats stand for,” said Rep. John Sarbanes of Maryland, who chairs the House Democrats’ Democracy Reform Task Force. He said his party has big ideas on immigration, health care, gun control and a number of other issues. But first, he said, “You have to establish this idea that you’re unrigging the system.”

Democrats can’t fight pharmaceutical companies on drug prices if the party is beholden to the industry’s donations, he said. More than 100 Democratic challengers have called on the party’s House leaders to embrace the idea.

One of them is Abigail Spanberger, a former CIA operative who is running to unseat Republican Dave Brat in Virginia’s 7th Congressional District.

“When we look at issues that are as great as education and health care and the cost of prescription drug prices and criminal justice reform, every piece of those issues does link back to what is the driving force behind legislation that’s coming out of Washington, what’s the driving force behind the purpose of those efforts whatever they may be,” Spanberger said during a recent phone call with reporters. “And I think that it’s up to us to take every action necessary to ensure that voters believe that it’s about them.”

Democrats share common policy priorities, of course, but if such an overhaul is the first order of business, it will quickly expose some of the rifts within the caucus.

Khanna said he expects the Progressive Caucus’ membership to serve as the party’s “fountain and engine for ideas” should Democrats reclaim the House. Early priorities could include, he said, a Medicare-for-all style of health care, a vote on an increase in the federal minimum wage to $15 an hour, and a $1 trillion infrastructure package to spur new jobs and improve the country’s roads, airports and rails.

Will Marshall, president of the Progressive Policy Institute, said the tack Congress takes doesn’t just depend on whether Democrats win control of the House or Senate, but by how much.

If the party comes in on a wave, then it will feel the pressure to take up big issues such as Medicare-for-all, rolling back the Republican tax breaks and addressing climate change and immigration. If they barely take control, the ambition could be lessened.

Regardless, Marshall said such issues as data privacy legislation could gain momentum in the next Congress: “There’s a growing feeling in the country that we need rules for privacy, to protect people’s personal information.”

Two-party power

Rep. Scott Peters of California, who heads the moderate New Democrat Coalition PAC, said there are issues on which Democrats of all persuasions agree, including protecting the so-called Dreamers, who came to the United States as undocumented minors; new campaign finance disclosures; and measures to ensure that all gun buyers are subject to background checks.

“I think it’s pretty obvious to all of us where we agree and that we agree a lot more than we disagree,” Peters said. When it comes to possibly working with the president, he isn’t sure what to expect.

“In two years, I haven’t seen a lot of interest on their side in doing that,” Peters said of the White House. He noted that the president has been “insulting to Democrats,” adding, “I don’t take any of that personally” and saying he’d work with the administration if it’s interested in tackling policies of interest in his district.

For his part, Trump said during an October appearance on Fox News that he believes Republicans will remain in charge of Congress. “And if we’re not, if we lose the majority in the House, which is always a possibility, we will probably just have to fight it out,” he said, adding that there are “a lot of haters” in the Democratic Party. “Now, can we get along? Maybe. And there’s a possibility. They want infrastructure, I want infrastructure; there’s something that can bring us together. We have a lot of things where there is commonality and it’s possible that we’ll even get along.”

Bipartisan collaboration between congressional Democrats and the president offers an intriguing possibility: Democrats could well be attacking the president with their investigative power — and certainly some will call for his impeachment — at the same time they try to strike legislative bargains with Trump.

“We would finally see what we’ve been promised the last year and a half: Infrastructure Week,” said Democratic lobbyist Anne Urban, who is with the K Street firm Urban Swirski & Associates.

At the same time, “Democrats have been really smart about keeping their powder dry on impeachment. But there’s going to be a whole lot of time spent doing investigations, and probably rightfully so. There hasn’t been anything close to exhaustive investigations done.”

Even some on the conservative, libertarian side say they welcome more oversight from Capitol Hill as a way to balance out executive power, which has been on the rise in recent administrations by presidents of both political parties.

“I welcome oversight of government programs, regardless of what letter goes behind the name of the chairman,” said Kent Lassman, who runs the Competitive Enterprise Institute, a libertarian think tank.

Matt Mackowiak, president of the Potomac Strategy Group, sees a political upside, eventually, to a House Democratic majority.

“I do believe they move to impeach the president in the first 90 days,” he predicted. That, along with a full slate of investigations, he said, “will help Trump get re-elected.”