From the USA.Gov blog:
2014 is a mid-term election year. All 435 seats in the U.S. House of Representatives are contested, as well as 36 of the 100 U.S. Senate seats. Gubernatorial elections will be held in 36 states and three territories, along with many state and local races.
Voting rules vary from state to state, but NOW is the time to make sure you are registered, your registration is up-to-date, and you’ve applied for an absentee ballot, if you need one.
Find out if your state allows early voting
Check your polling place and its hours
Schedule assistance getting to the polls, should you need it
See if your state requires official ID in order to vote
Don’t be caught off-guard and unable to vote on election day, check and be sure you have everything you need to cast your ballot.