Those days are long over, according to travel records and people familiar with the Rubio campaign’s plans. Rubio has traveled overwhelmingly by chartered jet since the Republican debate held in Milwaukee in mid-November.

Now, Rubio is spending an estimated tens of thousands of dollars every day to keep a Cessna Citation Excel plane by his side. The jet can comfortably sit a half-dozen passengers, with room for a couple more to squeeze on, if needed.

Without a single early-voting state to bank on, Rubio faces an imperative to cover long interstate distances quickly, perhaps more than any other candidate, as he splits his time and manages expectations among Iowa, New Hampshire and South Carolina.

“The difference between us and the other candidates is that some candidates are focused on only one place and we, of course, are campaigning in multiple places,” Rubio told the The Des Moines Register, shortly before boarding his jet for a rally and fundraiser in Dallas. “We’re supposed to fly out and our pilots say it’s going to get like really bad here in about an hour.”