TRENTON -- It's 6 a.m. in New Jersey, which means polls are now open for primary elections around the state -- including the day's big race, for the Democratic and Republican nominations to succeed Gov. Chris Christie as governor.

Polls are open until 8 p.m.

WHAT'S UP FOR GRABS?

All 120 seats in the state Legislature -- the body that makes New Jersey's laws -- are also on the ballot this year. And 19 of the 40 districts have competitive primaries for the Democratic and Republican nods for Senate and Assembly.

Plus, there are numerous county and municipal races.

But the most attention will likely be on the battle to replace Christie, a term-limited Republican who is set to leave office in January.

Six candidates are running for the Democratic nod: Bill Brennan, a retired Teaneck firefighter; Jim Johnson, a former U.S. Treasury official; Raymond Lesniak, a member of the state Senate from Union County; Phil Murphy, a former U.S. ambassador to Germany; John Wisniewski, a member of the state Assembly from Middlesex County; and Mark Zinna, president of the Tenafly council.

Five contenders are vying on the Republican side: Jack Ciattarelli, a member of the Assembly from Somerset County; Kim Guadagno, the state's lieutenant governor; Steven Rogers, a member of the Nutley commission; Joseph Rullo, an Ocean County small business owner; and Hirsh Singh, an Atlantic County aerospace engineer.

CAN YOU VOTE?

Only registered Democrats and registered Republicans are allowed to vote in the primaries.

But if you're one of the 2.4 million voters are unaffiliated in New Jersey, you can still cast a ballot -- by walking into your polling place and requesting a Democratic or Republican ballot.

That, however, means you're then registered with that party.

Visit the Department of State's Division of Elections website to see if you're registered. Voters who want to check if the are affiliated with a party can create a free online account with the Division of Election that allows them to access their detailed voting information.

Check out all the results and details tonight on nj.com

NJ Advance Media staff writers Matt Arco contributed to this report.

Brent Johnson may be reached at bjohnson@njadvancemedia.com. Follow him on Twitter @johnsb01. Find NJ.com Politics on Facebook.