In Minnesota's most-watched primary race, the leading Democratic candidates for U.S. Senate are ending the campaign with strikingly similar messages. Beneath those overlapping appeals is one of the party's clearest ideological tests this year and a contest between competing theories of electability. Peggy Flanagan, one of Minnesota's most prominent progressives, is betting Democratic primary voters want a more unapologetically liberal standard-bearer whose message can energize the party's core. With no credible third candidate on Tuesday's ballot, Minnesota's race could provide a clearer read on whether Democratic primary voters favor pragmatism or progressivism. But Stevens still won support from a substantial share of Democratic voters, highlighting the party's unresolved divide over what electability means.