The eyes of the nation will be on Georgia on Tuesday as voters finally settle a contentious U.S. Senate race between incumbent Sen. Saxby Chambliss and challenger Jim Martin that could determine the balance of power in Washington.

Voters also will decide two other statewide races, one for the Public Service Commission, the other for the state Court of Appeals. In Lumpkin County, voters also will choose a school board member.

But it is the Chambliss-Martin race that is expected to bring voters out again. In Hall County, more than 8,000 people voted during early voting, and interim elections director Charlotte Sosebee-Hunter said "a ton" of absentee ballots arrived by mail on Monday.

"I think (turnout is) going to be pretty good," she said Monday. "Probably less than the 40 percent I initially predicted, but still very, very good for a runoff."

Polls will be open from 7 a.m. until 7 p.m. across the state.

In the PSC race, Republican Lauren W. McDonald faces Democrat Jim Powell. In the Appeals Court race, Sara Doyle faces Mike Sheffield in the nonpartisan race.

The only local race still undecided is in Lumpkin County, where incumbent Stroud Stacy faces Susan L. Sockwell for the District 1 seat on the board of education.

About 14 percent of registered voters cast ballots early in Lumpkin County, said Kimberly A. Pruitt, the supervisor of elections. Pruitt said turnout might reach 40 percent, depending on Tuesday’s weather.

"The local race hasn’t been very heated," she said. "I think it’s mostly the senate race" that is driving turnout there.

In the November general election, Chambliss, a Republican, fell just short of the 50 percent threshold he needed to avoid a runoff with Martin, a Democrat. Libertarian Allen Buckley drew 3.4 percent of the vote. He has declined to endorse either candidate.

Statewide, the contest between Chambliss and Democrat Jim Martin has already attracted almost 500,000 early voters, and analysts say early statistics are promising for the GOP incumbent.

Less than 23 percent of the early voters who cast ballots for the runoff are black — a contrast from the surge of black voters in the run-up to the general election. Black voters made up more than 34 percent of the 2 million early voters before the Nov. 4 contest.

The runoff between Chambliss and Martin will help determine the balance of power in Washington where Democrats are just two votes shy of the 60 votes needed to prevent Republican filibusters. Georgia is one of two undecided contests. A recount is under way in Minnesota in the tight race between Republican Sen. Norm Coleman and Democrat Al Franken.

The Georgia race has been marked by ugly attack ads from both sides. Both campaigns also have brought out the political heavyweights to campaign with them.

Several Republicans have campaigned for Chambliss, including McCain and other one-time presidential candidates such as Rudy Giuliani, Mike Huckabee and Mitt Romney.

On Monday, Alaska Gov. Sarah Palin implored Georgia Republicans to back Chambliss in his hotly contested Senate runoff, telling a cheering crowd Monday that the first step in rebuilding the GOP begins with the Southern state.

Palin’s four stops for Chambliss — including one in neighboring Gwinnett County — underscored not only the stakes for the GOP in the Senate race but Palin’s popularity within the party. She has been mentioned as a possible presidential candidate in 2012 — a fact not lost on some Georgia voters.

Several thousand supporters waited in the cold to file into the James Brown Arena in Augusta. Vendors sold bright pink "Palin 2012" T-shirts and "Palin for President: You Go Girl" buttons. She was greeted like a rock star with chants of "Sa-rah!"

Former president Bill Clinton and former vice president Al Gore have both campaigned in Georgia for Martin, who toured the state Monday with prominent Georgia Democrats, including Rep. John Lewis of Atlanta. He capped the day with a state Capitol rally with the Atlanta hip hop artist Ludacris.

Martin had asked President-elect Barack Obama to campaign with him. Obama recorded a radio ad and automated phone calls for Martin but did not campaign in the state. Some 100 Obama field operatives traveled to the state to help with turnout.

Georgia’s last U.S. Senate runoff was in 1992. Democratic Sen. Wyche Fowler pulled more votes in the general election but lost to Republican Paul Coverdell in the runoff.

The Associated Press contributed to this report.