At least four Republicans have already announced a U.S. Senate run – Congresswoman Vicky Hartzler, Attorney General Eric Schmitt, former Governor Eric Greitens, and St. Louis attorney Mark McCloskey. Former Missouri House Speaker Pro-Tem Carl Bearden thinks Republicans might force former Democratic Governor Jay Nixon to jump into the U.S. Senate race.

Nixon ran for U.S. Senate in 1988 and 1998 – losing to Republicans Jack Danforth and Kit Bond.