Since it's pretty clear now that Bill Nelson could easily pull off a 2:1 victory, his coattails might be a factor. So:
1-Could this swing the governor's race?
2-Could this result in any House upsets a la Phil Crane?
Clay Shaw is the only House Republican I know of that is in a competitive race (and that is only by the fundraising, not by any polls, so I can't even tell how competitive it actually is). I can't think of any other Republican incumbent that is any trouble. Now, if we talk open seats, Republicans have two of them, so if Nelson does have any coattails, it will probably show up there.
Floridans seem to split their tickets somewhat, so it may or it may not be enough for Davis to win. Florida voted for Nelson the first time fairly comfortably in 2000 even while deadlocking on Bush and Gore. In 1988, Bush the elder won the state in a landslide, but Connie Mack barely squeaked to victory in the senate race. And in 2004, Mel Martinez ran three points behind Bush in his senate race.