Here are some of the important facts about Tuesday's election in New Hampshire:
RACES TO WATCH:
U.S. Senate: Incumbent Democrat Jeanne Shaheen is vying for a second term. She's up against Scott Brown, the former U.S. Senator from Massachusetts who is trying to become just the third person to represent two states in the Senate.
Governor: Maggie Hassan aims for a second, two-year term in Concord. The Democrat is opposed by Republican businessman Walt Havenstein in a race dominated by economic themes. It's rare for a first-term governor to be ousted.
U.S. House: In the 1st Congressional District, incumbent Democrat Carol Shea-Porter and Republican Frank Guinta face off for the third time. Annie Kuster, in the 2nd Congressional District, takes aim at a second term against Republican state Rep. Marilinda Garcia.
Legislature: Republicans in the state Senate currently have a 13-11 edge over Democrats. In the House of Representatives, a massive Republican wave could wrest control of the chamber from Democrats.
Polling places open between 6 and 11 a.m. depending on location. They close between 7 and 8 p.m.
As of Sept. 9, the number of registered voters by party was:
TURNOUT IN LAST MIDTERM ELECTION
In 2010, about 486,000 people cast ballots either in person or by absentee. That's slightly more than 50 percent of the total registered voters at the time.
SAME DAY REGISTRATION:
Eligible voters can register in person on Election Day. Voters will need to show proof of identity, age, citizenship and home address. These qualifications may be established by signing an affidavit.