First Read: “Biden’s task won’t be easy, however. He’ll be flanked on one side by Kamala Harris (who charged at him on bussing and segregationist senators in Miami), and one the other side by Cory Booker (who’s loaded for bear on Biden’s 1994 crime bill).”

“By the way, last night’s debate stage was all-white, while tonight’s is full of diversity – Harris, Booker, Castro and Yang.”

Jonathan Bernstein: “One interpretation is that Republicans don’t expect to return to a House majority in 2020. The current breakdown is 235 Democrats, 197 Republicans, one independent (the former Republican Justin Amash), and two vacancies last held by Republicans. So the party, if it holds the two open seats and wins back Amash’s, would only need to gain 18 others to restore its majority. A spate of retirements signals that they don’t really think that’s likely.”

“The thing about House elections is that expectations matter. A lot. The more a party thinks it’s going to be a good year, the more it will attract the resources needed to win, including strong candidates.”

“As for the timing? It’s possible that all the new retirements were long planned. It’s interesting, though, that they come after Robert Mueller’s testimony revived interest in President Trump’s scandals – and, perhaps more relevant, after Trump’s ‘send her back’ rally and his continuing series of bigoted tweets. It’s not crazy to speculate that one or more of these Republicans just didn’t want to campaign for reelection in that kind of atmosphere.”