Dittrich has carved out a career as a conservative DFLer in winning elections in her swing district in the northern Twin Cities suburbs.

Indian tribes have been a powerful force in Minnesota politics for nearly two decades, bankrolling major political party groups with hundreds of thousands of dollars for their campaigns. In 2011 they spread their money almost evenly between DFLers and Republicans.

A steady downpour didn’t keep Indian gambling workers from flocking outside the state Capitol in St. Paul last April. At least 1,500 people gathered outside on the building’s steps, some arriving by the busload from reservations hours away. Clad in raincoats and shielded by a canopy of umbrellas, workers thrust signs into the air that read, “Rural jobs count too” and “Don’t gamble with my job!”

Gubernatorial candidates have done a lot of handshaking with farmers attending this year’s Farm Fest in southwestern Minnesota.

Minnesota political observers were surprised by the DFL’s walloping performance at the polls in Tuesday’s state House elections. “I knew there would be Democratic gains ...