The battle for the soul of the Democratic Party is ramping up in Michigan as progressives look to clinch several key primaries in August. Progressive kingpins, Sen. Bernie Sanders (I-Vt.) and Rep. Alexandria Ocasio-Cortez (D-N.Y.), are set to hold rallies across the state this weekend with populist Senate candidate Abdul El-Sayed, who’s duking it out against centrist Rep. Haley Stevens (D-Mich.) for retiring Sen. Gary Peters’s…