The poll was conducted Aug. 11 among 418 registered likely voters in Florida, for a margin of error of plus or minus 5%. The data have been weighted for age, race, gender and political affiliation. This poll is one of a continuing series of polls of the presidential race for the Southern Political Report.

Dramatic turns of event could still spell unexpected trouble or prosperity for either candidate, in Florida or elsewhere. But for now, Obama simply isn’t ginning up quite enough support in Florida to turn all eyes to the state as the “tiebreaker” in November.

The likely reason is demographics. Florida doesn’t have as significant a percentage of blacks among its voting population as other big Southern states. Less well known is that it doesn’t have as many young voters either. Georgia, for example, is more stocked with the 18-29 year-olds that have flocked to the job market of Atlanta. And Florida’s young population is diluted as a percentage of the overall voting population by a glut of senior retirees.

Another telling take on this poll, and on those of other major pollsters who have felt the pulse of the electorate this summer across the country: The modest percentage of undecided voters – 5% in our poll – may be an indication that the electorate is polarizing into similar partisan patterns as four and eight years ago.

This may bode ill for Obama. He has carried his standard based on an appeal to voters who in the past have rejected the Democratic presidential candidate, but who supposedly are eager to jump the GOP ship because of disgust with George W. Bush.

It may be that McCain’s storied political independence from his own Republican Party in the past, combined with unease about Obama’s fitness for the presidency, are persuading disaffected Republicans and independents to throw in with him.

Obama’s full-court press of media buys in Florida was undoubtedly designed as much to force McCain to spend his comparatively modest resources here instead of elsewhere as it was meant to catapult Obama into the lead. But the strategy possibly could backfire if Obama’s spending spree doesn’t close the gap with McCain soon.