He left the state the night before the vote after piling on with Romney for over a week.
Santorum says he would rather spend his Saturday sitting at his kitchen table doing his taxes than campaigning in a state where the race for the Republican presidential nomination has become a two-man fight between Newt Gingrich and Mitt Romney.
Santorum was in Philidelphia Friday night, in Washington on Saturday night, and was with his daughter in the hospital on Sunday.
On Monday he returned to campaigning -- in the midwest, not Florida.
Santorum didn't run any ads in Florida, so he was hardly "piling on with Romney". much less for "more than a week".
Now, Santorum did beat Gingrich and Romney in the Florida debate; but you claimed he was "piling on Gingrich" and "non-stop attacking Gingrich". In fact, Santorum was low on money, couldn't run ads, and was a non-entity in Florida. He still pulled significant support, because Gingrich collapsed in the polls, but that wasn't Santorum's fault.