NEW YORK (CBSNewYork/AP) — Vice President Joe Biden believes there’s a chance Donald Trump could become the Republican presidential nominee.

“I would not be surprised if he is the nominee. I would be surprised if he got elected,” Biden told MSNBC on Thursday.

The vice president continued, “I think it is very possible he could be nominated. I would take him seriously.”

Biden told MSNBC he frequently gets asked how Trump is able to win over Americans. He said he takes Trump’s prospects seriously because Trump appeals to fear.

During a press conference Tuesday, President Barack Obama said he believed Trump will not be elected to the White House.

“I continue to believe Mr. Trump will not be president, and the reason is because I have a lot of faith in the American people,” Obama said.

Obama stated that people see what a serious job being president is, and it’s not just some sort of show.

“It’s not hosting a talk show, or a reality show, it’s not promotion, it’s not marketing. It’s hard,” Obama told reporters. “And a lot of people count on us getting it right.”

Trump shot back at Obama’s comment, telling CBS News’ Major Garrett that Obama would have been a one-term president if he ran in 2012.

“Obama is lucky I didn’t run last time because if I ran instead of [Mitt] Romney, he would have been a one-term president,” Trump said.

Trump got into a holy war of word with Pope Francis on Thursday after the pontiff said the billionaire wasn’t Christian because Trump wants to build a wall to keep immigrants coming in from Mexico.

“A person who thinks only about building walls, wherever they may be, and not building bridges, is not Christian,” he said. While Francis said he would “give the benefit of the doubt” because he had not heard Trump’s border plans independently, he added, “I say only that this man is not a Christian if he has said things like that.”

Trump, a Presbyterian and the front-runner for the Republican presidential nomination, responded within minutes.

“For a religious leader to question a person’s faith is disgraceful,” he said at a campaign stop in South Carolina, which holds a key primary on Saturday. “I am proud to be a Christian, and as president I will not allow Christianity to be consistently attacked and weakened.”

Trump also raised the prospect of the Islamic State of Iraq and Syria extremist group attacking the Vatican, saying that if that happened, “the pope would have only wished and prayed that Donald Trump would have been president because this would not have happened.”

In the latest CBS News poll, Trump is the favorite to win the South Carolina primary.

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