Congressional elections are held every two years on the Tuesday following the first Monday of November. The elections are always held in even numbered years.
In a presidential election year, the President, all members of the House and a third of the Senate face election. Two years later, the midterm elections occur. All House members are again up for election, along with another third of the Senate. Two years after that, another Presidential election is held, and the final third of the Senate is up for election, along with all House members. Members of the House of Representatives serve two-year terms, while senators serve for six-year terms.