Nov. 4 pivotal vote, where all 435 seats in the House of Representatives and a third of the Senate's 100 seats are at stake, will determine whether Republicans or Democrats control Congress.
From left, U.S. Republican Senator Rand Paul from Kentucky, Senate Minority Leader Mitch McConnell, McConnell's wife, former U.S. Secretary of Labor, Elaine Chao, celebrate at McConnell's midterm election night victory rally in Louisville, Kentucky, Nov.
Democratic U.S. Senator Jeanne Shaheen of New Hampshire celebrates her re-election victory over challenger Scott Brown at her midterm election night rally in Manchester, Nov. 4, 2014.
Voters fill in their ballots as they vote in the U.S. midterm elections at a polling place in Westminster, Colorado, Nov. 4, 2014.
A woman marks her votes on a ballot at a polling site in Mount Kisco, New York, Nov. 4, 2014. New Yorkers will decide to send back Gov. Andrew Cuomo for a second term.