Pete Buttigieg is officially running for president. He announced his decision to enter the crowded Democratic primary at a Sunday rally:

“My name is Pete Buttigieg. They call me Mayor Pete. I’m a proud son of South Bend, Indiana, and I am running for President of the United States,” he told the crowd.

The 37-year-old mayor of South Bend, Indiana, first made waves in January when he organized an exploratory committee. Since that time, he has unexpectedly become one of the better-known names in the race. As of the beginning of April, he had attracted $7 million in donations.

Buttigieg’s combination of identities—Midwestern mayor, Afghanistan veteran, openly gay and married—has helped him stand out from his fellow contenders. But they’ve also placed him at odds with some on the cultural left, as when Christina Cauterucci complained that he was not overtly gay enough. Such criticisms drew a sharp retort from The Washington Post‘s Drew Goins, who pointed out that an openly gay man’s “rising popularity in a presidential primary contest is a once-unimaginable accomplishment.”

Buttigieg shares many ideas with his fellow progressives in the race, even endorsing the notion of battling the conservative SCOTUS majority through court-packing. But he breaks with the pack on some issues—he opposes free college, for example, because he finds it difficult to support subsidizing the minority of Americans who earn more because of their college degree. He has also used his military service to promote a relatively non-interventionist foreign policy and to criticize “endless war.”

Bonus Link: Ira Stoll calls Buttigieg “the most interesting Democrat running for president.”