Democratic 2020 U.S. presidential candidate and South Bend Mayor Pete Buttigieg greets voters during a campaign stop at Portsmouth Gas Light in Portsmouth, New Hampshire, U.S., March 8, 2019.

Pete Buttigieg, a longshot contender to take on President Donald Trump in 2020, announced Monday that his campaign raised more than $7 million since the South Bend, Indiana, mayor declared his candidacy in January.

The fundraising total does not list the number of donors, and a complete public accounting is due April 15.

But the amount is turning heads, given Buttigieg's low name recognition — more than half of registered voters haven't heard of him.

Buttigieg, 37, seemed to come from nowhere to catapult into the middle tier of Democrats competing in the 2020 race for president.

Early polls have Buttigieg, who formed an exploratory committee in late January, tied with Sen. Amy Klobuchar, D-Minn., in seventh among declared and potential candidates.

Buttigieg tweet

"This is just a preliminary analysis, but our team's initial report shows we raised over $7 million dollars in Q1 of this year," Buttigieg wrote in a post on Twitter announcing the haul. "We (you) are out-performing expectations at every turn. I'll have a more complete analysis later, but until then: a big thank you to all our supporters."

Buttigieg announced in March that he had reached the donor threshold to qualify for the Democratic primary debates that will take place this summer. Under new rules established by the Democratic National Committee, candidates must receive contributions from at least 65,000 donors to make it to the debate stage.

The rest of the Democratic field is expected to begin releasing first-quarter fundraising totals Monday. Some candidates have already released early numbers.

Beto O'Rourke, a former Texas congressman who gained a national profile during his failed 2018 bid for Senate against GOP Sen. Ted Cruz, announced that he raised $6.1 million in the first 24 hours that he was in the race.

Sen. Bernie Sanders, I-Vt., announced a total just shy of $6 million for his first day and said he raised $10 million in his first week. Sen. Kamala Harris, D-Calif., announced that her campaign raised $1.5 million in its first 24 hours.

If Buttigieg were to win the White House next year, he would be the youngest president as well as the first openly gay one.

However, the record is bleak for sitting mayors seeking a major party nomination for president. The last one to do so was DeWitt Clinton, who ran in 1812 as a Federalist. Clinton, who had served as mayor of New York, lost to Democratic-Republican James Madison.

Rudy Giuliani and Martin O'Malley are among former mayors who recently mounted presidential bids. Giuliani, the former mayor of New York, raised more than $16 million in his first quarter in 2007, according to FEC records.

O'Malley, formerly the governor of Maryland and the mayor of Baltimore, whose aborted bid for president in 2016 lasted about nine months, raised a total of about $6 million in that time.

Former President Barack Obama, who eventually beat one-time Democratic front-runner Hillary Clinton in 2008, made a splash in April 2007 by announcing that his campaign had raised $25 million in the first three months of the year. Obama was then a U.S. senator for Illinois.