MSNBC’s “Morning Joe” co-hosts Joe Scarborough and Mika Brzezinski stopped by Stephen Colbert’s “Late Show” Tuesday night, handing the CBS series its best overnight ratings in more than two months.

Tuesday’s “Late Show” averaged a 2.9 rating in Nielsen’s local overnight markets. That is the show’s top mark since May 9, when Colbert pulled in a 3.1 rating with his “Daily Show” reunion episode.

Jon Stewart, John Oliver, Samantha Bee, Rob Corddry and Ed Helms helped Colbert out that night. The April 18 episode featuring Alec Baldwin also out-rated the “Morning Joe” appearance.

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The MSNBC stars’ appearance ended up being “The Late Show’s” third-best rating of the season on any evening.

During the visit, Scarborough announced that he’s leaving the Republican party to become an Independent. He was asked by Colbert why Republican members of Congress were so unwilling to turn on President Donald Trump. Scarborough responded that Republican officials had “betrayed their core values.”

“I am a Republican,” Scarborough said. “But I’m not going to be a Republican anymore. I’ve got to become an Independent.”

Scarborough served as a Republican representative for Florida’s 1st District from 1995 to 2001.

Also Read: 'Morning Joe' Accuses Trump of Lying for His Son: 'Part of a White House Cover Up' (Video)

“I think it’s inexplicable,” Scarborough said of the behavior of Republicans in Congress. “But this is well before Donald Trump was elected president that my party has betrayed their core values. I remember back in December of 2015 when Donald Trump supported a Muslim ban. I said on the air, ‘It’s very simple, it’s black and white.’ I said I could never vote for anybody in my party that would say they were going to ban people because of the god that they worshipped.”

Meanwhile, Mediaite columnist and top editor Colby Hall posted an opinion piece on Wednesday titled, “Joe Scarborough Disses Employer MSNBC By Announcing GOP Withdrawal on CBS.”

“The newly self-identified Independent raised the eyebrows of media insiders, however, by choosing to make the announcement not on the network that employs him, MSNBC, but rather on CBS’s ‘The Late Show with Stephen Colbert,'” Hall wrote.

Hall added: “It is worth noting that news of Scarborough’s announcement was broken by ‘Late Show’ Show Runner Chris Licht, who is the former Executive Producer for ‘Morning Joe’ and often gets credited for helping put that MSNBC morning show on the map. So perhaps Scarborough’s decision to go on CBS was a favor to an old friend… But the executive suites at NBC and NBC News are most likely shaking their heads in frustration.”