Barack Obama's lackluster debate performance last week has dramatically altered the presidential race in Florida, with Mitt Romney opening up a decisive 7 percentage point lead, according to a new Tampa Bay Times/Bay News 9/Miami Herald poll.

The survey conducted this week found 51 percent of likely Florida voters supporting Romney, 44 percent backing Obama and 4 percent undecided. That's a major shift from a month ago when the same poll showed Obama leading 48 percent to 47 percent — and a direct result of what Obama himself called a "bad night" at the first debate.