The months-long, $4 billion midterm election battle comes to a head with Tuesday's vote, and President Barack Obama's bloodied Democrats face an uphill struggle to hold their ground in Congress.
Republicans have the momentum and are ideally positioned to snatch a Senate majority that would put Obama's rivals in charge of both chambers of Congress during his last two years in the White House.
Polls show most Americans feel the country is on the wrong track, emboldening Republican candidates, who must either deliver a win or see their own agenda stymied by Senate leaders still loyal to an unpopular president.
"We are at a crossroads right now," Republican Joni Ernst said Friday at a campaign stop near the climax of a bruising campaign.
"Either we stay on the path that Washington has for us, or we take that right turn and start moving in the right direction."
Ernst and others have been joined on the campaign trail by Republican figureheads like Senator John McCain and 2012 presidential nominee Mitt Romney, who has crisscrossed the nation lending candidates his star power.
Democrats have tapped their political superstars as well, notably former president Bill Clinton, probable future White House candidate Hillary Clinton and popular First Lady Michelle Obama.
But the political landscape is tilting away from Democrats, with forecast models showing Republicans with good odds of winning the Senate.
"Within the last week to 10 days, we started to pick up some of the thunderstorms developing," Republican pollster Whit Ayres said this week. "We're starting to see the hints now of a building Republican wave."
All 435 seats in the House of Representatives are up for grabs, but with Republicans widely expected to maintain control there, eyes are on the Senate races, especially 10 key battleground states.
With his approval rating at just 43 percent, and lower in states with at-risk Democrat incumbents, Obama has largely avoided the campaign trail, opting instead to raise millions for Democratic candidates in closed-door fundraisers.
But he scheduled three stump stops for this weekend, including a visit late Saturday to Detroit.
"When you step into that voting booth, you are making a choice not just about candidates or parties. You're making a choice about two different visions of what America is about," Obama told the crowd.
And he warned of low Democratic turnout during the midterms, as in 2010, when Republicans romped to victory.
"This election is too important to stay home. Don't let somebody else choose your future for you," the president said.
"When we vote, we win."
The Republicans have repeated their mantra: "A vote for the Democrats is a vote for Barack Obama" as they have sought to make the midterm election a referendum on the president.
His policies, including "Obamacare," cuts in carbon emissions and the legalization of thousands of undocumented youths, are unpopular with the voters who will decide the key races.
Obama provided his opponents with an unintentional opening earlier this month when he assured that while he was not himself up for a vote, "make no mistake, these policies are on the ballot, every single one of them."
The statement hindered efforts by Democrats to distance themselves from Obama, but they still tried.
"The president's not relevant. He's gone in two years," Senate Democrat Mark Begich of Alaska, where the race is a toss-up, told the Washington Examiner.
Even as the New York stock exchange closed Friday at a record high, Republicans hammered home their message that Obama has let the economic recovery slip away.
"Six years on, their policies haven't gotten the country moving again," top Senate Republican Mitch McConnell, potentially the next majority leader, said.
"Events seem to keep spinning out of control, whether at home or abroad, with no one in the administration possessing a real handle on what to do next."
Should Republicans seize congressional control, Obama and Democrats will see several of their priorities shelved.
These include raising the minimum wage, mandating equal pay for women and safeguarding the environment.
Republicans, meanwhile, will seek to repeal Obama's health care reforms and roll back energy industry regulations.
But, with the 2016 presidential race on the horizon, the GOP will have an incentive to cooperate with Obama to get some key legislation, such as some kind of immigration reform, signed into law.
"Republicans will have to show they have the capability to govern," Republican Senator Bob Corker told a Tennessee newspaper.