The district most likely to see a competitive Democratic primary is Illinois’ 3rd, considering incumbent Daniel Lipinski only narrowly defeated Marie Newman 51 percent to 49 percent in this year’s primary. That result and Lipinski’s anti-abortion position will inspire another challenge. Further complicating matters, the incoming chairwoman of the Democratic Congressional Campaign Committee, Illinois Rep. Cheri Bustos, stood behind Lipinski this year and has said she strongly believes in supporting incumbents in primaries.

In Massachusetts, Seth Moulton has become a fascinating combination of a rising star who supports candidates around the country and a pariah who was part of the public opposition to Nancy Pelosi becoming speaker again. (Late Wednesday, Moulton and six other holdouts announced they would support Pelosi’s speaker bid after she agreed to back term limits for top party leaders.)

Primaries are nothing new to the 6th District congressman, considering he defeated Rep. John F. Tierney 51 percent to 40 percent in a 2014 primary. But Moulton hasn’t faced a Democratic challenger since. Outgoing state Sen. Barbara L’Italien recently told NBC10 Boston (before Moulton’s change of heart) she might challenge him in 2020, although she ran unsuccessfully in the 3rd District this year.

Rep. Kurt Schrader, who represents Oregon’s 5th District, is also taking heat for opposing Pelosi. (He was not among the Democrats who reached the agreement with her.) Milwaukie Mayor Mark Gamba told Oregon Public Broadcasting that it was a mistake for Schrader “to be in essence joining sides with the Republicans.”