Democratic presidential hopeful and mayor of South Bend, Indiana, Pete Buttigieg has endorsed Denver Mayor Michael Hancock’s campaign for reelection, in a video tweeted Tuesday by the sitting mayor of Colorado’s capital.

“Proud to call you a friend and pleased to endorse you in your re-election for mayor of Denver,” Buttigieg says in the 14-second video, tweeted at 6:10 p.m. by Hancock’s campaign account, @HancockforDenver.

“Thank you, Pete, for believing in the progress we are making here in Denver, and for all your work to move our nation forward,” Hancock tweeted.

Denver Mayor Michael Hancock is the presumptive front-runner in the municipal election that ends May 7, having raised more campaign funds than all five of his opponents combined through March.

He is facing a far more challenging re-election bid than four years ago when he breezed past six less-well known challengers with over 80 percent of the vote and avoided a June run-off election.

This year, he faces a set of better-known challengers who have tapped into an undercurrent of concern among voters over the pace and scale of growth and development and traffic congestion in the city over the last 8 years.

And he is running in a campaign season that has seen an unusually high number of candidates – 52 – in several competitive races for city council and city clerk.

In all, six candidates for Denver mayor appear on the ballot: Hancock and challengers Lisa Calderon, Stephan “Seku” Evans, Jamie Giellis, Kalyn Rose Heffernan and Penfield Tate III, who will appear at the top of the ballot as a result of a random drawing.

Buttigieg, 37, who started as an underdog in the 2020 Democratic race, has seen an uptick in support in recent weeks, and he’s now competing with several other contenders for third place in the 20-candidate field behind former Vice President Joe Biden and Vermont Sen. Bernie Sanders. He raised $7 million in the first quarter, eclipsing some of the better-known candidates in the race.

He supports some of the progressive proposals that have surfaced in the Democratic primary race, such as expanding the Supreme Court and doing away with the Electoral College. But he’s kept some distance from others, such as “Medicare for All” and a guaranteed income for the working class.

Buttigieg has been mayor of South Bend since 2012, and would be the youngest and first openly gay U.S. president. His northern Indiana community of about 102,000 people is best known for the nearby University of Notre Dame.

Colorado Politics’ John C. Ensslin and the Associated Press contributed to this report.