Seems unlikely that Obama would go to Florida to campaign for Murphy if he's so far behind.
Maybe, but it also seems unlikely that the DSCC would have pulled out of the race if their numbers said it was winnable.
But seriously, Rubio is not winning by this kind of margin. The "anyone who isn't Katherine Harris and doesn't eat babies will get 45% in Florida" rule still stands, Rubio isn't a good enough politician to take natural Democratic votes and Murphy isn't bad enough to lose those votes.
This must also be due to Marco Rubio's impressive debate performance on October 17 when he slammed Murphy for his family's money transfers from partnership with Donald Trump, accused him of not only flip-flopping but also metamorphosing and reminded him that he gropped a woman at the tits on a picture posted on Facebook.
I doubt it; the debate wasn't very publicized and not very watched. The reporting of it the next day in most of the big Florida papers didn't talk about a huge Rubio win; most of them seemed to say either both had won or that it was very close.
