AUGUSTA — Georgians voting in key congressional races Tuesday will decide whether the GOP gains two seats in the U.S. House, as Republicans looked to defeat the Deep South’s last white Democratic congressman and claim a new district built around Gov. Nathan Deal’s political turf.

The biggest race on the ballot featured Democratic Rep. John Barrow, who is fighting for a fifth term representing the 12th District after state lawmakers redrew boundary lines to carve out his political base in Savannah. A key question was whether Barrow would garner enough support from independents and Republican crossover voters to defeat state Rep. Lee Anderson, a farmer from Grovetown.

The new 9th District centered in Gainesville is packed with Republicans, giving state Rep. Doug Collins an edge over Democrat Jody Cooley, an attorney. Georgia gained the additional House seat from population growth recorded by the 2010 Census.

The election was the first using Georgia’s new 14-seat congressional map drawn last year. Republicans currently hold eight seats in the state’s congressional delegation to five for the Democrats.

Barrow, who moved to Augusta to stay in his district, raised more than $2.6 million for his re-election bid. He campaigned as a pro-gun, pro-business Democrat with a record of snubbing his party leaders and President Barack Obama on issues such as health care.

Anderson worked to persuade voters that Barrow was more two-faced than independent, citing mixed messages in the congressman’s own ads and fundraising letters. But Anderson, after stumbling in earlier GOP primary forums, refused to debate Barrow. And Barrow mocked Anderson for being a no-show in TV ads during the race’s final week.

Outside groups poured $5.7 million into the race. The National Republican Congressional Committee was one of the biggest spenders as it sought to help Anderson, who raised just over $1 million.

Elsewhere, three Georgia congressmen — Republican Reps. Austin Scott of Tifton, Lynn Westmoreland of Sharpsburg and Paul Broun of Athens — faced no opposition. Broun recently sparked controversy when he told a church group that evolution, embryology and the Big Bang theory were “lies straight from the pit of hell.” His critics urged voters to write-in Charles Darwin, the 19th century father of evolutionary theory, but those votes would not count.