Georgia voters head to the polls Tuesday to decide the party nominations for U.S. Senate seat, several contested Congressional contests, dozens of state legislative races and a Public Service Commissioner spot.

If this seems familiar, it is. Tuesday's vote will be the state's second primary in less than three months, since Georgians flocked to the polls on March 1 to vote in the presidential primary.

The polls are open from 7 a.m. to 7 p.m. and you can find your polling location here. Below you'll find a closer look at some of the top contests. And check out our voter guide.

Senate

Incumbent Republican U.S. Sen. Johnny Isakson faces two lesser-known challengers in his bid for a third six-year term: Mary Kay Bacallao and Derrick Grayson. Democratic leaders recruited investment fund manager Jim Barksdale to challenge Isakson, but first he must fend off Cheryl Copeland and John Coyne.

Read more about the race here.

U.S. House

Seven Republicans and two Democrats are vying to replace retiring Rep. Lynn Westmoreland in the 3rd District. A runoff is likely in that wild race.

Rep. Doug Collins faces former Rep. Paul Broun and three other challengers in the 9th District, the state's most conservative district. Catch up on the contest in this must-read story.

And freshman Rep. Barry Loudermilk drew four challengers in the GOP primary for the 11th, which covers a sprawl of northwest Atlanta. Here's why he could be in trouble.

State legislative races

Votes last year to raise taxes to shore up roads and bridges have put many influential Republican state legislators on the defensive. Find out about why House Speaker David Ralston and state Sen. Brandon Beach are among the top targets.

Down-ballot contests

A slew of important local offices are up for grabs, including the top spots in DeKalb and Cobb counties. And voters in Fulton and DeKalb will decide whether to continue a 1-percent sales tax to fund school construction and other education projects. Discover more about the Fulton vote and the DeKalb debate here.

Also, incumbent Public Service Commissioner Tim Echols faces two primary opponents: Kellie Pollard Austin of Lawrenceville and Michelle Miller of Warner Robins.

Things to know

You can vote in either party's primary, but make sure you bring some type of photo ID with you to the polls. (A list of the requirements are here.)

And remember that there’s a chance of a runoff in contests with more than two candidates. Georgia law requires election victors to get a majority of the vote, and if no one tops 50 percent, the two leading vote-getters will square off in a July 26 runoff.