Duncan, unsurprisingly, rejects the notion that Obama could lock down a victory for Martin, noting that McCain won Georgia. "The voters here have already rejected Barack Obama once," he said.
Merle Black, an expert on Southern politics at Emory University, said Obama would be taking a risk in coming to Georgia that could damage his political momentum.
"If Obama really thought that Martin was going to win, he'd make a quick hit and claim victory," Black said.
Indeed, Bill Clinton stepped into a similar situation here as president-elect in 1992, backing Democrat Wyche Fowler in a run-off. Fowler lost, and the episode was one of several reasons that Clinton's presidency was considered to have gotten off to a shaky start.
Obama, however, remains a large part of the race. Martin's television ads prominently feature the incoming president - a case of a Southern white politician invoking an African-American to woo voters. Only 26 percent of white voters backed Martin a month ago.
