Biden has been critical of super PACs in the past, and leveled criticism against money in politics during his campaign launch in May.
"Our Constitution doesn't begin with a phrase -- 'we the Democrats,' or 'we the Republicans' -- and it certainly doesn't begin with the phrase we the donors," Biden said in his speech in Philadelphia.
"As president, Joe Biden will push to remove private money from our federal elections. He will advocate for a constitutional amendment to overturn Citizens United and end the era of unbridled spending by Super PACs," Biden's Communications Director and Deputy Campaign Manager Kate Bedingfield wrote in a statement on Thursday, which was first reported by NBC News. "Until we have these badly needed reforms, we will see more than a billion dollars in spending by Trump and his allies to re-elect this corrupt president. And let's be clear: Donald Trump has decided that the general election has already begun."
"In this time of crisis in our politics, it is not surprising that those who are dedicated to defeating Donald Trump are organizing in every way permitted by current law to bring an end to his disastrous presidency. Nothing changes unless we defeat Donald Trump," Bedingfield added.
Trump has repeatedly made Biden the target of escalating attacks in recent weeks, and recently placed a $1 million television ad buy in the early voting states of Iowa, New Hampshire, Nevada and South Carolina targeting the former vice president.
In total outside super PACs and other groups from both sides of the political aisle spent roughly $1.4 billion during the 2016 election, according to OpenSecrets.
The reversal comes as Biden lagged significantly behind in the fundraising race in the third quarter of 2019, bringing in roughly $10 million less than his more progressive rivals for the nomination Sen. Bernie Sanders of Vermont and Sen. Elizabeth Warren of Massachusetts.
Dick Harpooltian, a South Carolina state senator and Biden ally, previously told ABC News that he expected a super PAC supporting Biden could be launched in coming weeks, and shrugged off concerns about the criticism that may come Biden's way from other Democratic candidates who have argued they perpetuate a corrupt system where campaigns are powered solely by cash.
"Everybody's always concerned about -- I mean, sort of the inside baseball people -- are always concerned about being criticized for where the money comes from. Nobody ever criticized for where the money comes from. Take Elizabeth Warren, she put $10 million from her Senate campaign into this primary campaign. Most of that money came from big corporate donors. You haven't heard a peep about it, nobody cares," Harpooltian said.
The announcement from Biden's campaign was immediately slammed by Sanders' campaign, who has been adamant that super PACs enable corporations and wealthy interests to exert undue influence on the political system.
"The former Vice President has been unable to generate grassroots support, and now his campaign is endorsing an effort to buy the primary through a super PAC that can rake in unlimited cash from billionaires and corporations. That's not how we defeat Trump. It's a recipe to maintain a corrupt political system which enriches wealthy donors and leaves the working class behind," Sanders Campaign Manager Faiz Shakir wrote in a statement released after the Biden campaign's announcement.
End Citizens United (ECU), a PAC dedicated to overturning the Supreme Court decision, also criticized the move by Biden's campaign Thursday.
"Vice President Biden has said repeatedly, including as recently as one month ago, that he would not embrace a single-candidate super PAC if he ran for president. Today he is breaking that promise," ECU President Tiffany Muller wrote in a statement. "I don't think we could say it as well as he did when he said ‘people can't possibly trust you' if you accept support from a super PAC."