Joe Biden ended Wednesday night's Democratic presidential primary debate by issuing a vexing call for supporters visit "Joe 30330" -- leading to confusion as to whether the former vide president promoting a website, text messaging number, or even the next millennium.

"If you agree with me, go to Joe 30330, and help me in this fight," Biden said in his closing statement.

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Within minutes of Biden's statement, the domain name Joe30330.com was purchased by an unidentified buyer. The website says it belongs to the campaign of "Josh for America," who calls himself the "first Gen Z'er to declare candidacy for this office."

Biden's campaign quickly clarified on Twitter that the candidate was urging supporters to "text JOE to 30330." His campaign had previously used that phone number for promotional purposes.

Nevertheless, the moment underscored concerns that the 76-year-old Biden may have lost his edge. Throughout the night, commentators pointed out that some of his answers seemed unsure, confused, or halting, even as Biden's substantive performance, on the whole, drew praise.

For example, Biden also warned that "eight more years of Trump will change America in a fundamental way," even though Trump can serve, at most, a single additional four-year term.

Biden also said he wanted to jail "insurance executives who totally oppose my plan in jail for the 9 billion opioids they sell," instead of drug company executives. He additionally called the Trans-Pacific Partnership the "TTP," rather than the "TPP."

And Biden at one point referred to Cory Booker as the next occupant of the White House: "The fact is that the bills that the president, excuse me, the future president, that the senator is talking about, are bills that were passed years ago and they were passed overwhelmingly," Biden said.

But by far, the text-message gaffe was the most enduring on social media.

"I can't believe we're only 30330 days away from FSU football," joked Washington Free Beacon reporter Alex Griswold.

"Biden: 'Get campaign updates on my MyTube page...'" wrote National Review's Kyle Smith.

Dave Itzkoff, meanwhile, pondered whether Biden had issued a clue befitting a movie like "Die Hard with a Vengeance," writing on Twitter, "Is 30330 a zip code where we'll find the next clue or something."

Earlier in the evening, protesters repeatedly interrupted the debate -- and at one point, demonstrators shouted down Biden with chants of "three million deportations."

That number referred to the approximate number of illegal immigrant deportations under the Obama administration -- which, on matters from health care to immigration policy, came under fire from the 2020 hopefuls as the debate continued.

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Biden did not directly respond to the demonstrations. He did say at one point during the debate, to the ire of some progressive commentators: "If you cross the border illegally, you should be able to be sent back. If we let people in, what should we say to the other immigrants wanting to come to the U.S. around the world? … People should have to get in line."

In perhaps his strongest moment on Wednesday, Biden confidently parried an attack by Sen. Kirsten Gillibrand, who seemingly suggested Biden thought women belonged in domestic roles.

After noting that he had raised several children as a single father, Biden pointed out that Gillibrand had repeatedly praised Biden on women's issues.

"I don't know what happened -- except you're now running for president," Biden said, to applause.