There's another logical reason: Paul never had much chance of doing well in Florida, which is the first contest in the primary season where only registered Republicans can vote. Paul does best in caucuses and "open primaries" where his army of devoted, young followers can vote Republican whether or not they have any strong allegiance to the GOP.
Florida, where Paul won just 3 percent of the vote four years ago, is the first real test of Paul among a true Republican electorate.
It's not likely to draw many young voters, who are the core of Paul's base. In New Hampshire and Iowa this year, at least 12 percent of the electorate was younger than 30, while 2008 Florida exit polls found only 7 percent of the GOP primary vote came from people younger than 30.
Florida is different
How else does the Florida primary electorate differ from Iowa, New Hampshire and South Carolina? Here are some comparisons, based on exit and entrance polls this year and Florida's four years ago:
Percentage of independents voting: Iowa, 23 percent; New Hampshire, 47 percent; South Carolina, 25 percent; Florida, 0 percent.
Voters aged 65 and up: Iowa, 26 percent; New Hampshire, 21 percent; South Carolina, 27 percent; Florida, 33 percent.
Self-described conservatives voting: Iowa, 83 percent; New Hampshire, 53 percent; South Carolina, 68 percent; Florida, 61 percent.