Neither Sanders’ campaign nor Warren’s responded to CNBC’s inquiries about their remarks. Biden’s campaign declined to comment on the remarks.
In less than one full day as a 2020 presidential candidate, Biden had already received more criticism from his fellow Democrats’ campaigns than any other candidate in his party.
“There’s a saying in politics: ‘You try to tackle the one with the ball,’” said Philadelphia-based Democratic strategist Aren Platt. “Until Biden emerged, I don’t think there was a clear ball runner.”
Both Warren and Sanders, who is running for president as a Democrat, have established reputations as critics and watchdogs of corporate interests and big banks.
Biden, on the other hand, was singled out for his corporate ties during his years in the Senate. With the money primary well underway, Biden’s early fundraising efforts have already drawn scrutiny from Democrats who have championed small-dollar donations.
“Because Biden been in this position for so long, the people who he was friends with, his contemporaries, have risen to the highest levels,” Platt said. “That’s Joe Biden’s social circle … the challenge for him and his campaign will be bridging that gap.”
Among the Democrats running in 2020, Warren, a former Harvard law professor, has been among the most vocal about policy. She has shared her plans for breaking up tech giants including Amazon and Apple, as well as raising revenue by slapping a new tax on corporate profits over $100 million.
Sanders proffered legislation last October to break up the big banks.
Predictably, Trump and Republicans have not held back in taking early swings at Biden.
“I’m a young, vibrant man!” Trump, 72, told reporters outside the White House on Friday. “I look at Joe, I don’t know about him. I don’t know.” Biden is 76.
Republican officials have laid out their own strategy on Biden: compare Trump’s economic record with Biden’s during President Barack Obama’s two-term presidency.