Who will wield the speaker's gavel? Will Democrats launch impeachment proceedings if they take the House? Can the GOP hold the Senate and, with it, the power to confirm President Trump's nominees?
While these questions dominate the headlines going into Tuesday's elections, the historical gale-force winds of change that come with the first midterms of any presidency bring yet another question: Will some of the most well-known House Republican figures be around next year?
From members of leadership to lawmakers seen as rising stars in the party to GOP incumbents who have simply been around a long time and become fixtures on cable television, numerous influential Republican lawmakers are seeing their political survival threatened by the "blue wave" Democrats hope will crash through Washington next week.
They include: the chairman of the House Intelligence Committee who has played a key role in the Russia investigation, a fervent Trump supporter under federal indictment for allegedly swiping campaign funds for personal use, and the No. 4 House Republican.
While a Democratic takeover of the House is not assured, it is a virtual certainty that many GOP incumbents will make this year their last on Capitol Hill.
“A lot of incumbents aren’t ready for their districts changing underneath them and for the wave that is coming from the Democrats,” Cal Jillson, a political science professor at Southern Methodist University, told Fox News.
One of the highest-profile members facing a competitive House race is Rep. Devin Nunes of California. Nunes, the Republican chairman of the House Intelligence Committee, has put himself in the national spotlight for his outspoken views on Special Counsel Robert Mueller’s Russia investigation and his steadfast defense of President Trump.
Nunes’ time in the limelight has paid off for him in terms of fundraising, but there are concerns that his focus on national issues over local issues – and his time away from his rural, agricultural district – could hurt him come Election Day.
"One of the criticisms of his constituents have been: he is not accessible," Lisa Bryant, a professor at Fresno State, told NPR.
Nunes, whose campaign did not respond to a request for comment from Fox News, remains the front-runner. But while he won his re-election bid in 2016 by double-digits, a recent poll found the California lawmaker with just an 8-point advantage over Andrew Janz. Janz, Nunes’ Democratic challenger, has never before run for office, but his campaign has raised more than $8 million – a huge amount for a Democrat in a historically red district.
Janz echoes the complaint by some constituents in California’s 22nd District that Nunes spends too much time thinking about Washington and not enough time on issues important in the Central Valley.
"The Russia issue is relevant insofar as it takes away the political capital that he has now in Washington to focus on what people care about here," Janz told NPR. "I think that this race is about taking back the Central Valley."
Another California Republican in the hot seat this election season is Rep. Duncan Hunter – he's not being accused of spending too much time in Washington, but of spending campaign funds on himself.
Hunter, whose 50th District includes parts of San Diego County and Riverside County, is under federal indictment, along with his wife, for allegedly stealing $250,000 of campaign funds for personal use. While Hunter has stepped down from three House committees, he has refused to drop out of the congressional race and has called the indictment “pure politics.”
“My campaign did make mistakes,” Hunter told Fox News’ Martha MacCallum. “There was money spent on things, not by me but by the campaign, and I paid that back before my last election. I paid back $60,000 dollars after I did an objective audit. This is pure politics.”
California’s 50th Congressional District is considered a relatively strong Republican district and Hunter – a major supporter of Trump – has previously enjoyed broad support from his constituents. But the federal indictment has wreaked havoc on his reelection campaign, with polling earlier this week showing Hunter’s once double-digit lead shrinking to 3 points over his challenger, former Obama White House aide Ammar Campa-Najjar.
The poll, conducted by SurveyUSA for The San Diego Union-Tribune and 10News, found that more than half the voters in Hunter’s district believe he broke the law and only 26 percent of his constituents have a favorable opinion of him.
Meanwhile, GOP Rep. Dana Rohrabacher, who has represented California in Congress since the 1980s, is in the race of his life against Democrat Harley Rouda. Fox News' Power Rankings rates the contest as a "toss-up."
Two states north, an influential moderate Republican lawmaker also faces a tough re-election campaign as she tries to balance her loyalty to a Republican Party that has moved further right under Trump with her own criticisms of the administration.
Cathy McMorris Rodgers, who has represented eastern Washington’s 5th District for 14 years and is the highest-ranking Republican woman in Congress as House GOP Conference chairwoman, is in a statistical dead heat in the race against her Democratic opponent, economist Lisa Brown.
A recent poll conducted by Brown’s campaign found that Brown had 46 percent of the vote while McMorris Rodgers had 49 percent, with a margin of error of 4.3 percentage points.
“Cathy McMorris Rodgers has been saying things that make a lot of moderate conservatives really nervous,” Jillson said.
In a press release attached to the poll, Brown said that her rival “delivers talking points” from the Republican Party and is “increasingly losing touch with the priorities of eastern Washington.”
The incumbent's campaign has cast Brown as a far-left candidate out of step with the district, with a spokesman saying, “People in Eastern Washington want freedom, opportunity, self-determination, and free markets. Lisa Brown does not reflect those values.”
McMorris Rodgers’ balancing act between toeing the party line and taking a more moderate stance goes back to the 2016 presidential campaign and her lukewarm endorsement of then-candidate Trump. The president has apparently put that aside and recently tweeted a “Strong Endorsement” of the Washington lawmaker, calling her “an incredible leader.”
Since the 2016 election, McMorris Rodgers fluctuated between praising the president on a number of policy positions while also voicing her displeasure with his language toward women and the administration’s decision to implement tariffs on imported steel and aluminum. But in the closing weeks of the midterm election season, she seems to be shifting back into the Trump orbit – bringing Trump surrogates like Counselor to the President Kellyanne Conway and Vice President Pence to the state for fundraisers.
It’s not just in California and Washington – states with formidable Democratic leanings – where GOP incumbents are having re-election troubles. In Republican strongholds like Iowa, Utah and Texas, many incumbents are feeling the pressure.
Outspoken Iowa GOP Rep. Steve King faces an increasingly tough time after his controversial comments and endorsements came in question following Saturday's massacre at a Pittsburgh synagogue. King has come under fire from both Democrats and, this week, the head of the National Republican Congressional Committee for his history -- including tweets he's posted endorsing a white nationalist candidate for Toronto mayor and praising a nationalist party in Austria with Nazi ties.
King responded Tuesday by saying, “These attacks are orchestrated by nasty, desperate and dishonest fake news. Their ultimate goal is to flip the House and impeach Donald Trump. Establishment Never Trumpers are complicit.”
Democrats are already hoping to flip two of Iowa's four congressional seats, and the turmoil surrounding King has them thinking they could take his seat as well. It's a tough task in a district that President Trump won by 27 percentage points. But even some Republicans acknowledge King is in for a tough challenge from Democratic challenger J.D. Scholten.
In Utah, Rep Mia Love – the only black Republican woman in the House, and a rising star in the party – is in a dead heat race against Salt Lake County Mayor Ben McAdams and has been hit by her opponent with accusations of financial improprieties.
And in Texas – while much of the attention this midterm season has focused of Republican Sen. Ted Cruz’s battle against Democrat Beto O’Rourke – Rep. Pete Sessions, the moderate chairman of the House Rules Committee and former chairman of the National Republican Congressional Committee – holds a slim 1-point lead over Democrat Collin Allred as he, like McMorris Rodgers, balances his more moderate stances with his party’s agenda.
“Pete Sessions is similar to McMorris Rodgers in that neither of them are offensive in any sense,” Jillson said. “That would make them a shoo-in in any election year, but not this year.”
The Associated Press contributed to this report.