If you paid attention to the 2018 midterm elections, Tuesday night’s Democratic debate might have brought back some memories.

Ten presidential candidates faced off in the first night of the second series of debates, which aired on CNN. And many of them cited Democrats’ 2018 victories as proof that that candidate had the right stuff to win back the White House next fall.

“Democrats flipped 40 Republican seats in the House, and not one of those 40 Democrats supports the policies of our front runners at center stage,” said former Colorado Gov. John Hickenlooper, referencing the liberal proposals of Massachusetts Sen. Elizabeth Warren and Vermont Sen. Bernie Sanders.

Hickenlooper’s comments kicked off clashes between the liberal and more moderate candidates. He was mostly correct that the Democrats who flipped the House tended to be centrist — seven of the 43 Democrats who won GOP-held seats co-sponsor Medicare for All legislation and just one co-sponsors the Green New Deal.

The reference to the victorious House Democrats was not the only time the 2018 midterms loomed over the conversation. Here are four ways the 2018 elections influenced the two-and-half hour debate:

1. Health Care! Health Care! Health Care!

Ask Democrats how they flipped the House in 2018, and they’ll likely say it was by talking about health care. The issue is still top of mind for voters, so it’s no surprise that it was the first topic of the debate. While Democrats in 2018 zeroed in on GOP attempts to repeal much of the 2010 health care law, on Tuesday the presidential hopefuls largely aimed their fire at each other.

Warren and Sanders defended their support for Medicare for All, while former Montana Gov. Steve Bullock said people with problems today “can’t wait for a revolution”and former Maryland Rep. John Delaney slammed their “impossible promises” that limit would eliminate private insurance.

Democrats are still hoping to leverage health care in 2020, even as it divides the large primary field. As the presidential hopefuls went back and forth Tuesday night, the Democratic National Committee sent a text to its phone list that read, “Trump has repeatedly tried to take health care from Americans who need it most. Our eventual nominee will fight to protect and expand coverage — not limit it.”

While the candidates showed differences on how far they would take the expansion of publicly provided insurance, the one-minute answer, 30-second response format meant they were often cut-off and even the best-informed viewers could have had a hard time following. Still,  Republicans are expected to go on offense on the issue by using Medicare for All to portray the field as supporting socialist policy. Ahead of the debate, Trump’s campaign rolled out a new TV ad attacking Democrats’ health care positions, saying, “They’re all the same.” 

2. All about the money

It was reminiscent of 2018 that a conversation about gun control on Tuesday night quickly bled into a discussion about campaign finance reform.

“What is broken is a political system that allows the NRA and other large big money to come in and make things not happen when the majority of people are for it,” Minnesota Sen. Amy Klobuchar said. The National Rifle Association has been a frequent boogeyman for Democratic conversations about money in politics, and it was again Tuesday night.

Klobuchar noted that although students from Parkland, Florida, helped spark a movement after the shooting at Marjory Stoneman Douglas High School, and the Democratic-controlled House passed background check legislation, it’s unlikely to go anywhere in the Senate “because of the money and the power of the NRA.”

Depending on their districts, some of those Democrats who helped win the House majority talked about gun control. But even more talked about getting money out of politics — but not just for the sake of campaign finance reform. In 2018 Democrats connected that message, frequently conveyed through a pledge to reject corporate PAC money, to other issues, such as opioid addiction, rising prescription drug costs, and climate change.

End Citizens United, a liberal PAC, helped craft a narrative about how money in politics affects issues voters care about. While some party leaders were skeptical about the salience of that message at first, Democratic strategists now credit it with helping candidates in red districts win over many of the same voters who were drawn to Trump’s pledge to “drain the swamp” in Washington.

All of the Democratic presidential candidates are refusing corporate PAC money, and the fact that the number of individual donors is being used this year as a metric to qualify for the debates shows the extent to which Democrats are prioritizing small-dollar fundraising.

Former Texas Rep. Beto O’Rourke said he’d ban political action committee contributions to any member of Congress, which would have sounded unfamiliar before 2018.

South Bend, Indiana, Mayor Pete Buttigieg used this conversation to try to argue that he’ll be the candidate of even bigger systemic change, including reversing a Supreme Court ruling that opened the door to more corporate money in campaigns.

“Of course we need to get money out of politics,” he said, as if that idea was already well-accepted. “Does anybody really think we’re going to overtake Citizens United without constitutional action?”

Bullock, a late entrant to the race who’s made campaign finance a signature issue, used that moment to tout his own successes.

“You can make changes,” he shot back at Buttigieg. As Montana attorney general, Bullock led a challenge to the Citizens United decision, and as governor, he signed legislation requiring outside groups to disclose where their money comes from.

3. Jury’s still out on strategy

Democrats largely agree that to win back the White House in 2020, they need to win states that Trump narrowly carried in 2016, including Wisconsin, Michigan and Pennsylvania.

But Democrats remain divided on the best strategy for winning those states: peeling off Trump supporters, winning over independent swing voters, energizing Democratic base voters, or all of the above. Democrats who flipped GOP seats last fall found a split record of success: 21 flipped seats Trump won in 2016 while 22 flipped seats that Clinton won.

Warren said Democrats’ best strategy is “being the party of big structural change” and to “give people a reason to show up and vote.”.

Others suggested liberal policies could turn off critical swing voters. Hickenlooper sharply criticized Medicare for All and the Green New deal, saying, “You might as well FedEx the election to Donald Trump.”

Bullock said Trump voters will be key to winning the White House in 2020. He frequently mentions that he’s the only candidate who’s actually won statewide in a Trump state — a claim he repeated in his first debate appearance. Trump carried Montana by 21 points in 2016, while Bullock won re-election that same year by less than 4 points.

Bullock’s success in Montana, however, is why many Democrats would prefer he stay there to run for Senate. The national party is without a top-tier challenger to GOP Sen. Steve Daines, who is up for re-election next year.

Klobuchar also touted her past ability to win over Trump voters.

“I’m from the Midwest and I have won every race, every place, every time,” she said. “I have won in these red districts,” she repeated later in the debate.

Klobuchar won re-election last fall by 24 points, despite Democrats losing two long-time Democratically-controlled House seats in the state, which Trump had carried in 2016.

“There are people that voted for Donald Trump but that aren’t racist,” Klobuchar said. “They just wanted a better shake in the economy. And so, I would appeal to them.”

O’Rourke also made the case that his increasingly diverse home state of Texas is now a battleground after he almost defeated GOP Sen. Ted Cruz in 2018. Cruz beat O’Rourke by 3 points in a state that Trump won by 9 in 2016. Democrats also flipped two GOP House seats in the suburbs in 2018, and are targeting more seats in Texas in 2020.

“Those 38 electoral votes in Texas are now in play and I can win them,” O’Rourke said, suggesting his 2018 playbook could translate to a winning national campaign.

4. Young and the restless

Tuesday’s debate featured the youngest candidate in the race, Buttigieg, 37, and the oldest with Sanders, 77.

“I don’t care how old you are,” Buttigieg said before suggesting America could be leading a trend of electing fresh new leaders — with the vision to match.

The midterms may have helped shift the conversation about age in politics. At age 29, New York Rep. Alexandria Ocasio-Cortez became the youngest woman ever elected to Congress. Iowa Rep. Abby Finkenauer is only slightly older. Both women are part of a relatively young and diverse freshman Democratic class.

Two of the young Democrats in Congress, however, won’t be debating this week. California Rep. Eric Swalwell dropped out of the presidential race, and Massachusetts Rep. Seth Moulton didn’t qualify.

Many of the Democratic candidates who found success in 2018 were new to politics. They decried gridlock in Washington, and some presidential hopefuls who don’t work in the nation’s capital made similar cases Tuesday night.

“The frustration with what’s going on in Washington is they’re kicking the ball back and forth,” Hickenlooper said during an exchange on immigration.

Buttigieg also criticized congressional inaction on gun violence and immigration, as well as with authorizing military action abroad. He said Congress has been “asleep at the switch” in exercising its war powers.