Libertarian Party presidential candidate Bob Barr could wedge an opening for Barack Obama in Georgia, some experts say.

Mr. Barr, a former Republican congressman from Georgia who became a Libertarian, was nominated Sunday at the party's national convention.

His bid jars the previous consensus that the state is a shoo-in for the Republican nominee in waiting, Sen. John McCain of Arizona, and it raises the possibility that instead of bypassing Georgia in favor of more closely contested states, he and Mr. Obama will campaign here often.

"I would be shocked if the Obama camp doesn't key in on Georgia as a possible upset possibility," said Matt Towery, an Atlanta pollster and analyst.

Mr. Towery said in Georgia, that's even more probable "given ... that most other Southern states appear to be less competitive for ... Obama."

Mr. Obama, expected to be the Democratic nominee, was the first candidate to set up a campaign office in Georgia.

Obama spokeswoman Amy Brundage would not comment, and McCain spokesman Jeff Sadosky would say only that "we're very confident of our ability to carry the state."

Michael Badnarik, the Libertarians' 2004 nominee, drew less than 1 percent of the vote in Georgia. But Mr. Barr was picked by 8 percent in a recent statewide survey done for Mr. Towery; Mr. McCain had 45 percent, with Mr. Obama at 35 percent.

Mr. Towery and others say Mr. Barr and his anti-tax, anti-regulatory message appeal strongly to some Georgia conservatives.

"Whatever votes Bob Barr gets will reduce the McCain total," said Charles Bullock, a University of Georgia political science professor.

Mr. Towery said Mr. Barr is better known than most Libertarians in Georgia because of his political career, national talk-show stints and published articles. But not everyone is so bullish about the impact on the race in Georgia.

"I'd expect that as the election nears, the Barr vote share will decline, as some people now inclined to vote for him will return to McCain in hopes of defeating the Democrats," Mr. Bullock said.