WASHINGTON -- Vice President Joe Biden on Thursday warned that real estate mogul Donald Trump could win the Republican presidential nomination.

“I think it's very possible he could be nominated and, depending on how this all plays out, I would take him seriously in terms of being able to win,” Biden told MSNBC's Rachel Maddow. “He's appealing to fear. He's appealing to that old expression: ‘In the land of the blind, the one-eyed man is king.’

“I'm not very good at prognosticating, but I would not be surprised if he's the nominee. I would be surprised if he got elected,” Biden added.

﻿Biden's concern about Trump's electability went further than President Barack Obama, who earlier this week said he couldn't see Trump winning the GOP nomination. It also marks a shift from Biden's assessment of Trump in December, when he dismissed Trump's candidacy as "showmanship." Biden did, however, express concerns at the time about Trump's proposal to ban all Muslim immigrants, calling it "a very, very dangerous brew for America."

Biden, a devout Catholic, on Thursday also addressed Trump's feud with Pope Francis, who condemned Trump as "not Christian" for his proposal to build a massive wall along the U.S.-Mexico border.

FABRICE COFFRINI via Getty Images

“Pope Francis, Donald Trump,” Biden said, weighing the two options by gesturing with each hand. “That’s not a hard call for me. Not even close.”

He called Trump's border wall idea "inconsistent with what we are."

“The idea of the United States erecting wall for the world to see makes a lie of everything we say about ourselves," Biden said. "It's a little bit like why the president and I feel so strongly about closing down Guantanamo. It's inconsistent with what we are. Why do people like America? I like America for what we stand for.”

Editor's Note: Donald Trump is a serial liar, rampant xenophobe, racist, misogynist, birther and bully who has repeatedly pledged to ban all Muslims -- 1.6 billion members of an entire religion -- from entering the U.S.

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