Colorado Gov. Jared Polis, other local Dems, line up behind Kamala Harris

President Biden's stunning decision to drop out of the 2024 presidential race opens the door for Colorado Gov. Jared Polis to jump into it.

• Yes, but: The likelihood of that outcome is narrowing as Democratic leaders nationwide close ranks around Vice President Kamala Harris ' candidacy and Polis himself endorses her .

Why it matters: The popular two-term governor is one of a handful of Democrats whose name has been floated in the media to replace Biden at the top of the ticket.

State of play: For now, Polis is supporting Harris, who has been viewed as the obvious successor and secured Biden's endorsement .

• In a post on X early Sunday evening, Polis called Harris "the next President of the United States."
• Polis' office did not immediately respond to Axios Denver about whether he'll run.

What they're saying: Most of Colorado's congressional delegation — including U.S. Reps. Diana DeGette , Jason Crow , Joe Neguse and Brittany Pettersen — also formally endorsed Harris.

• Other delegation members, such as U.S. Sens. Michael Bennet and John Hickenlooper , released statements thanking Biden for his service, but stopped short of endorsing other candidates.

Flashback: Leading up to Biden's withdrawal, most of Colorado's Democratic party leaders were apprehensive about backing the president's quest for a second term.

The intrigue: Denver Mayor Mike Johnston told us he would support Harris as president as well as Michigan's Democratic Gov. Gretchen Whitmer.

• "I think she's done a really compelling job as a governor of Michigan, leading a purple state and delivering results in a way that's, I think, practical and inclusive," Johnston told us in an interview last week.
• "I would put her at the top of the list of other folks I'm very impressed by," he added.

The other side: Republican U.S. Rep. Lauren Boebert on X called Biden's term a " total failure " and said former President Trump will "resoundingly defeat" his Democratic opponent, whomever is chosen.

• "The Democratic Party should never claim to be the party of 'democracy' ever again. They just disregarded the entire primary process," she added .
• Jeff Crank, a Republican running for the 5th Congressional District seat based in Colorado Springs, demanded Biden "resign immediately, or the cabinet must invoke the 25th amendment for the sake of our country," he said in a statement .
• The amendment allows a vice president, with support from a majority of the cabinet, to declare a president unable to discharge their duties and make the vice president the acting president.

What we're watching: Whether Biden's exit will prompt Polis to enter the race with less than a month before the Democratic National Convention .

Editor's note: This story has been updated with new details throughout.