Criticism of former President Obama by Democrats running for president came as a surprise to Joe Biden. In remarks Thursday, Obama's former vice president told reporters that during the primary debate Wednesday night, "I was a little surprised at how much incoming there was about Barack, about the president ... I don't think there's anything that he has to apologize for. It kind of surprised me the degree of the criticism."

Biden was the most targeted candidate on stage Wednesday night, fending off questions about his health care proposal to build on the Affordable Care Act, and the high number of deportations during the Obama administration. Biden repeatedly defended Obama's record on immigration, noting that he instituted the Deferred Action for Childhood Arrivals program.

"I hope the next debate we can talk about our answers to fix the things that Trump has broken, not how Barack Obama made all these mistakes. He didn't," Biden said Thursday. He added that repeated criticism of the former president was a "game to make sure that we hand the Republicans the election."

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Biden also said he looked forward to attending a debate with fewer candidates on stage, which would allow for longer responses to questions and rebuttals to direct attacks. The rules to qualify for the next primary debate in September are far more stringent -- candidates need to have 130,000 unique donors and register at least 2% support in four polls. So far, only seven candidates, including Biden, have met those qualifications.

"The idea that we don't actually have a chance to explain our policies, in less than one minute ... that's not a debate," Biden said. "I'm looking forward to getting to a place where we can actually exchange ideas."

Asked if there was anything he would change about his performance on Wednesday night, Biden brought up his exhortation to debate watchers to "visit Joe 30330" during his closing statement, leaving viewers confused.

"I would've said to 'text'" Joe to 30330, Biden said with a laugh.