All of the nonbillionaire Democratic presidential candidates except Bernie Sanders are facing a cash crunch after blowing through their war chests in the month of January.

Businessman Tom Steyer and former New York City Mayor Michael Bloomberg are bankrolling their own bids, and the Vermont senator’s massive small-donor base is keeping him with far more cash than his rivals — $16.8 million at the end of the month despite spending slightly more than the $25.1 million he raised.