He endorsed Joe Biden and socialist candidate for NE-2 Kara Eastman
https://journalstar.com/news/state-and-regional/federal-politics/mccollister-endorses-biden-invites-other-nebraska-republicans-to-join/article_ee4589ac-bd92-524b-8615-5ef5fb0432ef.html
https://omaha.com/news/state-and-regional/govt-and-politics/kara-eastman-receives-endorsement-from-sen-mccollister-republican-who-called-out-trump/article_64e423ce-352b-59bb-8e4e-7514abc2d4c3.html
