Mayor Pete is in the money.

Pete Buttigieg, the mayor of South Bend, Ind., officially announced he is running for president Sunday afternoon, and within hours his campaign coffers were overflowing.

“Some news: since delivering his announcement speech, our grassroots supporters have invested more than $1m in @PeteButtigieg’s campaign,” Buttigieg’s communications adviser Lis Smith tweeted Sunday night.

Smith tweeted the stat shortly after 7 p.m. ET. Buttigieg’s 2020 bid was made official about 3 p.m. ET.

PETE BUTTIGIEG FORMALLY ANNOUNCES 2020 PRESIDENTIAL RUN

In a speech announcing his run, Buttigieg highlighted both his progressive values and Midwestern upbringing.

"I ran for mayor in 2011 knowing that nothing like Studebaker would ever come back—but believing that we would, our city would, if we had the courage to reimagine our future," Buttigieg said in a speech inside South Bend's Studebaker auto plant. "And now, I can confidently say that South Bend is back."

He added: "There’s a long way for us to go. Life here is far from perfect. But, we’ve changed our trajectory, and shown a path forward for communities like ours."

The 37-year-old Afghanistan War veteran, who has been exploring a White House run since January, now joins the field of a dozen-plus rivals and one that is likely to reach 20 or more.

MAYOR PETE BUTTIGIEG CALLS OUT BIG TECH'S 'MONOPOLY POWER'

BUTTIGIEG CONTRASTS HIMSELF WITH BIDEN AND SANDERS

Over the past few months, Buttigieg has appeared frequently on national TV news and talk shows and developed a strong social media following with his message that the country needs "a new generation of leadership."

Buttigieg's poll numbers have climbed. Some polls put him behind only Vermont Sen. Bernie Sanders, who sought the party's nomination in 2016, and former Vice President Joe Biden, who has not yet said he's running.

Buttigieg's campaign raised more than $7 million in the first three months of this year, a total eclipsed by Sanders' leading $18 million, but more than Sens. Elizabeth Warren of Massachusetts, Amy Klobuchar of Minnesota and Cory Booker of New Jersey, among others.

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Buttigieg would be the first openly gay nominee of a major presidential party; he married his husband, Chasten, last year. He would be the first mayor to go directly to the White House. And, he would be the youngest person to become president, turning 39 the day before the next inauguration, on Jan. 20, 2021. Theodore Roosevelt was 42 when he took office, while John F. Kennedy was 43 and Bill Clinton 46.

Fox News’ Andrew O’Reilly contributed to this report.