Rep. , D-Minn., has dropped out of the 2024 presidential race and endorsed President Joe Biden.

"Americans were demanding an alternative, and democracy demands options. But it is clear that alternative is not me," Phillips wrote on social media platform X on . "And it is clear that Joe Biden is OUR candidate and OUR opportunity to demonstrate what type of country America is and intends to be."

Phillips' exit from the Democratic field came hours after GOP candidate Nikki Haley announced her own decision to suspend her presidential bid, effectively cementing the widely predicted November rematch between President Joe Biden and twice-impeached former President Donald Trump.

Phillips' announcement whittles down an already uncompetitive Democratic primary.

On Super Tuesday, Biden racked up wins in state after state, though he lost the U.S. territory of American Samoa to little-known Democrat Jason Palmer. Biden's campaign has been in general election mode for weeks, kicking into high gear after the president swept New Hampshire and South Carolina.

Phillips hinted at an announcement on Super Tuesday, cryptically noting that he would be "making decisions over the coming days."

"As the only candidate not losing to Donald Trump in any poll, I'm grateful for the beautifully orchestrated outpouring of wishes to end my mission to ensure his defeat," Phillips wrote in an on Super Tuesday. "I'm touched by the thoughtfulness, and will be making decisions over the coming days about how we can best fulfill that objective."

Phillips previously pledged to stick out the campaign through the Democratic National Convention. As funds ran low, the campaign had to pare down operations to keep afloat, cancelling scheduled events and laying off staff in February.

"I found it almost impossible to raise enough to do this campaign the way I want," Phillips said in a social media post on Feb. 16.

With most of the financing from his own pocket, Phillips, 55, launched his long-shot presidential bid in October and ran as a younger alternative to Biden, who is 81 years old.

Beyond Phillips' age, however, the third-term congressman and former Talenti gelato CEO failed to distinguish himself from the incumbent president. In Congress, he voted in with Biden's agenda, and he did not otherwise express major policy differences with Biden.

In January, Phillips said that if he were elected president, might include Tesla founder Elon Musk and hedge fund billionaire Bill Ackman.

Another potential challenger to Biden, Sen. , D-W.Va., formally announced on Feb. 16 that he would not run for president after a monthslong flirtation with a third-party bid.

With the Democratic nomination firmly in his grasp, the president has already turned to the general election, which appears likely to be a rematch between Biden and Trump.

Though Biden's age was not enough to singlehandedly keep Phillips' campaign afloat, it is still a top vulnerability as the general election nears.

Recent found that concerns about Biden's age and mental acuity were still top issues for respondents, even as his marks improve on other major voter priorities such as the economy.

Questions about the president's age and mental acuity have grown, especially since the Feb. 8 release of a Department of Justice report by special counsel .

The report examined Biden's handling of classified documents, and cleared the president of criminal liability for documents that had not been properly stored. But what captured the public's attention was Hur's description of Biden as a "sympathetic, well-meaning, elderly man with a poor memory."

"My memory is fine," a visibly angry Biden said at a press conference hours after the Hur report was released. "I'm an elderly man, and I know what the hell I'm doing."

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