Tonight on The Last Word: Democrats retain the majority in the U.S. Senate. Also, President Biden says he's unsure if there are enough votes to codify abortion rights. Plus, Democrats flip a long-held GOP House seat in Washington. And Democrats add seats in legislatures of key 2024 battleground states. Sen. Gary Peters, White House Chief of Staff Ron Klain, Rep.-elect Marie Gluesenkamp Perez, Jessica Post and Simon Rosenberg join Lawrence O'Donnell.