All of the attention will be on who wins the presidency, but voters will also be choosing new members of Congress – where laws are passed – when they fill in their ballots.
Congress consists of the House of Representatives, where all 435 seats are up for election, and the Senate, where 34 seats are being contested.
Republicans currently control the House, which initiates spending plans. Democrats are in charge of the Senate, which votes on key appointments in government.
These two chambers pass laws and can act as a check on White House plans if the controlling party in either chamber disagrees with the president.
