After a divisive campaign marked by fierce clashes over race, immigration and other cultural issues, Americans began casting votes on Tuesday to determine the balance of power in the US Congress and shape the future of Donald Trump's presidency.
Democrats need to win two seats to claim the Senate majority.
Currently Congress is dominated by the Democrats, but a reshuffle could see the Republicans take control.
Not only do Democrats have the most to lose, but in order to secure a majority in the Senate, will have to keep every one of their current seats and then gain another two.
Tuesday is Democrats' last, best chance to stifle President Trump's agenda before he completes his first term.
Waters, who is black, doesn't have a leadership position like Schumer or Pelosi, but is nearly always mentioned in the same breath as them at Trump's rallies.
President Donald Trump: "I don't know about it. Democrats are inviting caravan after caravan, illegal immigrants to flood into our country". "No nation can allow its borders to be overrun". I don't care what they say.
'I don't care. They can do whatever they want and I can do whatever I want, ' he responded. "That is an invasion of our country".
Trump echoed what he's been saying for weeks as he stumps for Republican candidates for the House, Senate and governor's mansions: Democrats will throw America in reverse. A CNN poll gave Democrats the largest margin, a 13-point advantage; an NBC/Wall Street Journal poll had the Democratic lead at 7 points.
President Trump shakes hands with House Majority Leader Kevin McCarthy during a rally this summer.
"Whatever you can do to ensure victory tomorrow, get out and vote, get your family, get your friends, get everybody to get out and vote", he told the supporters on the line. When you participate in the political process, you can be a check on bad behavior. "There's so many things that are pushing this in unconventional ways", Klein said.
FILE - Florida Democratic gubernatorial nominee Andrew Gillum, left, and Senator Bill Nelson (D-FL), right, listen to former President Barack Obama as he addresses the media and supporters as they stump for votes at a rally in Miami, Florida, Nov. 2, 2018.
What will the outcome of the midterm elections be?
With massive turnout from early voters, the Texas senate election is going to be a big one - and if it goes Democrats' way, a nightmare for Republicans.
Unlike 2016, there is no Electoral College in the midterm elections to distort the popular will of the American people.
In the final hours before the election, Mr Trump has criss-crossed the country, pitching for key candidates in critical states such as Florida and Missouri.
Like Ms. Swallows and Ms. Kent, more than 30 million Americans already have voted in a midterm election expected to draw unprecedented numbers by the time polls close on November 6 night. "I think there will be no difference here". It will also signify a shift from past cycles when they were reluctant to defend the ACA from Republican assaults because of its perceived unpopularity. RealClearPolitics puts Trump's average approval at about 43 percent, with 53 percent disapproving.
Georgia - Many will also be watching the race for governor in the southern state of Georgia.
In an interview with ABC on Monday, the president said he wished he had had "a much softer tone" throughout his presidency. "That is particularly true when a president is unpopular, as this president is".
Democrats saw the election in equally historic terms. They are also poised to make history with a number of LGBT candidates and Muslims up and down the ballot.
This looks increasingly unlikely, but Donald Trump's position has been cited as a core reason people are voting against the Republicans in the House.
But as he touched down in IN for the second leg of his final-day tour, even Trump conceded that the House may slip from his party's grasp. "Anything that gets done will have to be a bipartisan basis".
If Democrats take control, they can limit what he does in the rest of his two years.