Sen. Bernie Sanders out-raised former Secretary of State Hillary Clinton by nearly $13 million for the month of February, despite him being behind in terms of delegates.

A source close to the Sanders campaign told The Washington Post that the Vermont senator managed to bring $43.5 million while the former secretary of state collected just $30.1 million.

While the Sanders campaign has taken in more money, it has also spent more — leaving Clinton with a cash advantage for the month of March as the campaigns respectively spent $17.2 million and $30.8 million.

The self-proclaimed Democratic Socialist outpaced Clinton in January as well, having taken in $20 million to Clinton’s $15 million.

Sanders faces an uphill battle to win the nomination at July’s Democratic National Convention in Philadelphia, but campaign aides told Politico they hope superdelegates could secure him the position.

“Our plan on this is we’ve got a long way to go, and we’ve got to demonstrate that Bernie’s the strongest candidate,” Sanders strategist Tad Devine told the publication. “We believe that slowly we can win support for people who aren’t for someone, or who are softly for her, and then we can reach out more.”

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