WASHINGTON – U.S. President-elect Barack Obama and his defeated Republican rival, John McCain, are engaged in somewhat of a rematch. The two are trying to help their respective parties win a razor-close U.S. Senate race in Georgia. 

McCain has accepted an invitation to attend a rally in Atlanta on Thursday for Republican Sen. Saxby Chambliss, while Obama aides are being dispatched to the state to provide a hand to Democratic challenger Jim Martin, a former state senator.

A Dec. 2 runoff is being held because neither Chambliss nor Martin obtained the majority required under state law in the Nov. 4 election to be declared the winner.

A Democratic aide said no final word has been given on whether Obama will visit Georgia on behalf of Martin. A Republican aide said there’s a chance former vice presidential nominee Sarah Palin may show up for Chambliss.

While Obama won the White House, McCain took Georgia.

Georgia is one of three states where tight U.S. Senate races have yet to be decided.