Morning Joe: Trump wouldn’t even run in 2020 if Mark Cuban challenged him in GOP primary

MSNBC's Joe Scarborough says that deep down, President Donald Trump knows that voters would never have picked him if they had a better option.

The "Morning Joe" host said the president is likely to face a Republican primary challenger in 2020, but he said one long-shot candidate could chase Trump out of the race.

"(Voters) are with Donald Trump only until they're no longer with Donald Trump," Scarborough said.

He said Republican voters backed Trump only because the other option was Hillary Clinton, but that won't be the case when the president seeks re-election.

"When it's Donald Trump or Ben Sasse, or Donald Trump or James Langford, or Donald Trump or Jeff Flake, or a lot of other Republicans that jump in -- or a business person," Scarborough said.

Scarborough said Trump would be too scared to face one potential challenger.

"Donald Trump's biggest fear is it may be Donald Trump vs. Mark Cuban in the Republican primary," Scarborough said. "He doesn't want that. In fact, he probably wouldn't run if Mark Cuban ran in the Republican primary, and a lot of people around him don't think that will happen."