Former House Speaker Newt Gingrich thinks California Sen. Kamala Harris is "most likely" to be nominated to the Democrats pick to challenge President Trump in the 2020 presidential race. Gingrich, speaking to CBSN on Monday, said Harris' base of California and general likability make her a serious contender for the nomination.

"She's very articulate and I think a likable person, and I think that she represents a new generation in a way that [Joe] Biden and [Bernie] Sanders are going to work very hard to be able to match," Gingrich added. The lifelong Republican said that while Biden and Sanders both have the advantage of national name recognition, the larger dynamic of the Democratic party as it stands now leans so far left that it presents a potential challenge for traditional candidates like the former vice president and the Vermont senator.

"It's also [open] to newer faces in a way that I think Sanders has a hard time coping with." Gingrich's forecasting isn't far off either, according to recent polling by Monmouth University, Harris placed third, behind both Biden and Sanders with 8 percent support.

But Gingrich also thinks rising star South Bend Indian Mayor Pete Buttigieig may be the "most dangerous opponent" to Mr. Trump.

"He's from the Midwest, he's a mayor of a small town, he has no particular public record, he can be like [former president] Jimmy Carter used to be, a Rorschach test of you paint on him what you want," Gingrich said of Buttigieg. He conceded, however, "I think he probably has a hard time getting through the process."

Gingrich also talked about the Capitol. The former House speaker, who has written a new novel, "Collusion," commended his former colleague and current House Speaker Nancy Pelosi for her handling of the aftermath of Robert Mueller's Russia report amid calls from her own party to pursue impeachment proceedings.

"I think she's done exactly the right thing," Gingrich said of Pelosi on "CBS This Morning" on Monday.

Newt Gingrich on Nancy Pelosi doing "exactly the right thing" with Mueller report, new novel "Collusion"

Gingrich, who served as speaker from 1995 and 1999, including the time when President Bill Clinton was impeached, said that based of his own experience, "With a solid report -- guilty on 11 counts -- the country ultimately listened to the arguments and said 'no,' and the Senate refused to convict."

"You have a Republican Senate, the odds against conviction are overwhelming and I think Speaker Pelosi is trying to say to her House Democrats, 'You want to maximize the political advantage. You don't want to go into an ambush where we look hyper-partisan.'"