ST. JOSEPH, Missouri — When Josh Hawley decided to run against two-term incumbent Democrat Claire McCaskill in 2018, there was plenty of skepticism that he could dislodge her from the U.S. Senate seat she had held since 2006.

McCaskill, now a very liberal MSNBC contributor, was considered at the time a centrist member of her party as well as a tough-as-nails campaigner who, in a last-minute effort to hold her seat, ran a radio ad saying she was “not one of those crazy Democrats.”