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

Colorado Gov. Jared Polis quashed rumors of his own presidential bid Sunday evening by endorsing Vice President Kamala Harris hours after President Biden's decision to drop out .

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

Yes, but: In the hours since Biden's bombshell announcement, Democratic leaders nationwide have begun closing ranks around Harris' candidacy.

State of play: Polis said Sunday evening he's " thrilled " to support Harris, who has been viewed as the obvious successor and secured Biden's endorsement .

• In a second social media post , Polis called Harris "the next President of the United States."

What they're saying: The entire Colorado Democratic congressional delegation — including U.S. Sens. Michael Bennet and John Hickenlooper , along with U.S. Reps. Diana DeGette , Jason Crow , Joe Neguse and Brittany Pettersen — also endorsed Harris.

• Bennet and Hickenlooper were the last two to bend the knee to Biden's endorsee.

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.

Go deeper ... Polis says he's open to being Harris' running mate

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

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