Among those watching the White House race most closely a year from Election Day are those who stand to gain the most from the top-of-the-ticket contest.

House and Senate candidates from both parties know their fates are closely tied to the fortunes of their parties’ respective presidential nominees and the tenor of the national conversation next November.

“Obviously the national environment is something that, to a certain extent, we have very little control over,” NRSC Communications Director Andrea Bozek said. “So our mentality is to prepare for the worst-case scenario.”

What is the worst case scenario?

For Senate Republicans, it’s voter turnout of the kind that sent President Barack Obama to the White House in 2008.

For House Democrats, it’s the status quo.

“I’m not sure we can do much worse,” a Democratic consultant told CQ Roll Call, audibly knocking wood on the other end of the phone. With a 30-seat deficit, Democrats don’t have a path to winning the House majority.

The Senate, though, is in reach. Democrats are defending 10 seats. Republicans are defending 24, and they occupy nine of Roll Call’s list of the top 10 seats most likely to flip.

Because the Democratic Senatorial Campaign Committee landed nearly every recruit it wanted , Democrats have a real chance to capitalize on presidential-year turnout to net the five seats needed to win the majority (or four if they win the White House).

“It’s really hard for me to see us getting the presidency without a Senate majority to go with it,” a Democratic strategist said Wednesday.

Finding five seats without winning the presidency, he said, “would be really extraordinary.”

Democrats Want Trump at Top of Ticket

Democrats’ offensive line begins with the six competitive states Obama carried twice: Illinois, Wisconsin, Pennsylvania, New Hampshire, Ohio and Florida. In five of those states, they’re targeting members of the class of 2010 who rode to Congress on the anti-incumbent GOP wave.

While non-politicians are leading this year’s GOP presidential polls, the “year of the outsider” was six years ago in the House and Senate.

“A lot of our incumbent senators have their own brand,” a GOP strategist said of the class of 2010. “That’s been a very smart strategy because that will help separate them from whatever will happen next.”

What emerges next will be a GOP nominee. Democrats are gleeful about a possible Donald Trump nomination, and they’ve expanded their recruitment map to reliably red states such as Missouri and Arkansas to maximize their possible gains.

“Even if we’re just making them spend money to keep Arkansas, we’re winning,” a Democratic strategist said. “That’s true of Kentucky as well.”

Regardless who emerges as their nominee, Republicans admit their map is challenging. They have just two pick-up opportunities, Nevada and Colorado, and in the latter, they’ve yet to land a credible challenger to Sen. Michael Bennet.

Most Republicans agree that Sen. Mark S. Kirk’s days in the Senate are numbered. Representing deep blue Illinois, and with a penchant for saying what shouldn’t be said, Kirk has been outraised by Democratic Rep. Tammy Duckworth, who’s also dominating her primary opponents.

After Kirk, Democrats feel most confident about knocking off Wisconsin Sen. Ron Johnson.

Republicans have been quick to seize on former Democratic Sen. Russ Feingold, who’s running against Johnson, former Pennsylvania Rep. Joe Sestak and former Ohio Gov. Ted Strickland as “retread” candidates with losing records. But a presidential year presents a ticket-splitting quandary for Republicans.

‘How Are You Going to get Hillary Clinton voters?’

New Hampshire hasn’t voted for a Republican presidential candidate since 2000, and with Democrats having landed the female recruit they wanted , Sen. Kelly Ayotte has to carve out a more moderate path to election than she did in 2010. Earlier this week, she became the first Senate Republican to back the EPA’s clean power plan .

“Looking at the Obama states, part of the thinking needs to be, ‘How are you going to get Hillary Clinton voters?’” a Republican strategist said.

The Buckeye State has a shorter blue streak at the presidential level. And with an $11 million war chest, and an opponent with a political record in the state, Sen. Rob Portman may have an easier path to re-election.

Besides Nevada, Florida is the one competitive open-seat race in this year’s landscape. Republicans have a crowded field clamoring to replace Marco Rubio, but Democrats aren’t without their own fractures.

As in Illinois and Ohio, Democrats point to the fundraising win posted by the DSCC-backed candidate in Florida, Rep. Patrick Murphy, to quell attacks of intraparty division.

“For something that could have been problem, it does not seem to be unfolding that way,” a Democratic strategist said of Murphy’s primary fight with Rep. Alan Grayson. Of course, that could always change should Grayson cut his campaign a bigger check.

If there’s a weak spot in Democratic recruitment, it’s North Carolina. Like Republicans in Colorado, Democrats failed to land their top recruits in the Tar Heel State.

Asked about recruiting troubles, parties in both states answer with one name: Cory Gardner. The freshman senator didn’t enter the 2014 Colorado Senate race until March of that year, keeping alive the hope there’s still time for a stellar candidate to emerge.

But because of the presidential race, neither party is under any illusion their incumbents in either state are untouchable.

“A blow out for [Bennet] is not a double-digit win,” one Democratic strategist said. “A blow out will be 5 or 6 points.”

It’ll Still Be the Republicans’ House

Republicans don’t have to worry about losing their majority, but they do need to minimize their losses.

They know they’ve got their work cut out for them in districts Obama carried, especially in the northeast. Seven of Roll Call’s top 10 most vulnerable House members are Republicans.

Despite struggling to lock down viable candidates in a handful of districts that go their way at the presidential level, Democrats have assembled a strong roster across a swath of competitive districts.

And ongoing redistricting efforts in Florida, Virginia and North Carolina could make several more seats competitive for Democrats.

They’re banking on Trump and Ben Carson remaining at the top of national polls to help them pick off vulnerable Republicans in places such as Florida, Iowa and Michigan and win open-seat contests in Minnesota’s 2nd district and Michigan’s 1st district.

“ In some of the competitive races, you have a pretty typical older white male Republican types with very conservative records,” one Democratic consultant said. “ They’re doing what they can to play moderate at the moment. But it’s easier to call their bluff on who they really are if there’s an out of the mainstream character at the top .”

“[Marco] Rubio would be a really tough candidate,” she said of the Florida senator running for president. “States where we might have some solid inroads could be questionable based on the draw he might have in particular communities,” she added.

Republicans hope to make gains in Florida’s 2nd and 18th districts, Minnesota’s 8th, Nebraska’s 2nd and Arizona’s 1st districts.

“There aren’t too many more places we can expand the map,” one GOP strategist said.

Related:

Democrats Nearly Run Table in Senate Recruitment

Democrats Prepare for the Unlikely in Senate Races

Rematches Invite ‘Retread’ Label, Familiar Theme s

Conservative Outside Groups Playing Defense This Cycle

Roll Call Race Ratings Map: Ratings for Every House and Senate Race in 2016

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