WASHINGTON, March 20 (Reuters) - U.S. Democratic presidential candidate Bernie Sanders outraised rival Hillary Clinton in February but spent at a faster pace, leaving him with less money, the Washington Post reported on Sunday.

Sean Rayford via Getty Images

Sanders raised $43.5 million in the month, compared with Clinton, who raised $30.1 million.

The U.S. senator from Vermont has amassed much of his fundraising haul from online donations driven by supporters contributing small amounts of money.

While Sanders raised more than Clinton, he also spent more than the former secretary of state. At the end of February, Sanders had $17.2 million in cash remaining, the Post said. Clinton had $31 million, according to her campaign.

(Reporting by Ginger Gibson; Additional reporting by Emily Stephenson and Grant Smith; Editing by Peter Cooney)