For nearly two years, Trump's rule-breaking, sometimes chaotic administration has enjoyed a largely free hand from the twin Republican-controlled chambers, but the midterms could finally see his wings clipped. A president who often battles his own party, would face a far less forgiving opposition.
"Everything we have achieved is at stake tomorrow", he said during a blitz of three final rallies. If Trump manages to pull off a victory in terms of retaining control of one or both Houses, it will be seen as a validation of his stand that poor migrants and refugees from other countries are a threat to the peaceful life of the American people and send out a clear message to the world on what the original "country of migrants" now thinks on that issue.
Trump blamed the political vitriol on election season. "'Don't worry about it, I'll just figure it out.'" Bracing for defeat, he said on a conference call with supporters Monday that he wasn't sure the election could fairly be considered a referendum on him.
Elections for all the members of the House are held every two years.
Sabato's Crystal Ball, a nonpartisan political newsletter run by the University of Virginia Centre for Politics, predicted the Democrats would gain 34 seats in the House, 11 more than the 23 they need to form a majority. Other committees are plotting aggressive oversight of Trump's administration and his web of business interests. His current approval rating among Republican voters has reportedly touched a whopping 89 percent. If Republicans keep their majority, McCarthy could be the next speaker of the House. But a narrowed majority would also exacerbate divisions over policy - and continued unified control could leave the GOP facing the blame for gridlock.More news: Cameroonian govt promises swift response over abducted students in northwest region
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"Clearly there's an very bad lot on the line in terms of the legislative agenda", said Republican consultant Josh Holmes. That's nowhere near as well as they were doing in the GOP/Clinton seats, where Democrats led virtually all of the contests. They view Democrats eagerness to investigate the president as a blessing in disguise in the run-up to 2020. He said Democrats encouraged chaos at the borders because it was good politics.
"The peril is subpoenas, investigations, legal bills and headaches", he said. He has been campaigning for the Democratic Party, focusing on preserving the Affordable Care Act and warning of attempts by the Republicans to strip welfare measures to find money to offset the soaring deficit.
White House aides have discussed floating popular legislative issues, such as infrastructure, to tempt Democrats and test the unity of the Democratic opposition. In 1996, 1988, 1980, 1972, 1968 and 1956, one party controlled all of Congress, but voters picked the other party for the White House. Democrats are defending 10 Senate seats in states Trump won; all of them contain large numbers of Obama-Trump voters.
In the closing weeks of the midterms, Trump has unleashed a no-holds-barred effort to boost Republicans as he dipped into the same undercurrents of unease that defined his 2016 campaign.
The bid to make it all about Trump is a gamble, as is his growing shift from touting economic successes to bitter - critics say racist - claims that the country is under attack from illegal immigration.
Republicans are favoured to retain their slight majority in the U.S. Senate, now at two seats, which would let them retain the power to approve U.S. Supreme Court and other judicial nominations on straight party-line votes.
Much has been written about the Democratic party's surge in support in America's suburbs, especially among college-educated women.