Joe Biden is reporting that he raised $21.5 million for his presidential campaign in the second quarter. That has the former vice president trailing Pete Buttigieg, who was virtually unknown a few months ago.

Biden's campaign announced his second quarter fundraising total on Wednesday.

Buttigieg, the South Bend, Indiana mayor, reported taking in $24.8 million for the quarter, $3 million more than Biden.

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Vermont Sen. Bernie Sanders says he raised $18 million.

Colorado Sen. Michael Bennet says he raised $2.8 million.

President Donald Trump's campaign announced a massive $105 million take for the quarter, which reflects the incredible resources at his disposal as he prepares to fight for reelection.

Reports to the Federal Election Commission are due July 15.

The numbers will be an indicator of the health of the candidates' campaigns.

Most White House contenders haven't revealed their fundraising numbers.

TEGNA Staff contributed to this report.