Nate at FiveThirtyEight has a good analysis of the broad swath of recent polls and particularly these polls out this morning from Quinnipiac showing Barack Obama with leads in Pennsylvania, Ohio and Florida. It's only one poll. But this is the first poll that has shown Obama ahead in Florida against either McCain or Clinton. Most models for an Obama win don't include Florida, though Obama's campaign certainly seem intent on contesting it. But that's McCain's firewall. If he can't win Florida, the electoral map starts to look very bleak. Even having to fight for it would put McCain in a hole.