While much of the country's attention is on the presidential race, Democratic and Republican candidates are also vying for seats in congressional contests and races for state governors.
Thirty five of the 100 U.S. Senate seats are up for grabs, while all 435 seats in the House of Representatives are being decided. Terms of senators are six years, while House members serve for two.
Democrats currently hold a majority in the House of Representatives, as well as in the Senate, where they have a razor-thin margin. Democrats are expected to bolster their majority in Congress and possibly obtain the 60 Senate seats needed to obtain a filibuster-proof majority.
Besides the congressional contests, 11 states are also holding gubernatorial races. Those states include Montana, New Hampshire and West Virginia.
Voters in some states will also be asked ballot questions.
In South Dakota, residents will be asked if they support a ban on abortion, except when a mother's life is at risk, and in cases of rape and incest. California voters will be asked whether parental notification is required before a minor can get an abortion.
In Arkansas, residents will vote on a ban on couples not in a valid marriage, which includes gay couples, from adopting or being foster parents. Voters in Arizona, California and Florida will be asked if they support a ban on gay marriage.
Some information for this report was provided by AP.