Washington (CNN) Former Vice President Joe Biden closed his Democratic presidential debate performance Wednesday night by telling viewers to "go to Joe 30330," apparently mixing up a phone number for supporters to text with a website not affiliated with his campaign.

"If you agree with me, go to Joe 30330 and help me in this fight. Thank you very much," Biden said.

Viewers swiftly took to social media to express their confusion. Biden later tweeted a similar call to action, this time with an instruction to text.

Biden said in the tweet, "If you liked what you heard tonight, text JOE to 30330 and let's get to work." The text returns a fundraising pitch from his campaign.

Asked by reporters Thursday if there was anything he would have done differently in the debate, Biden cited the misspoken line.

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