In Detroit last night, Republican presidential candidates sparred over some important and not so important issues in the last debate before the Michigan primary on Tuesday. And tomorrow, voters in around a half a dozen states will head to the polls. Right now, Trump has amassed 329 delegates. Cruz has 231, Rubio 110 and Ohio Governor John Kasich has 25. But Kasich says we haven’t yet heard from his “turf,” aka the Rust Belt. It’s a region hit hard by the decline of manufacturing jobs, which were once synonymous with union jobs. What’s happened to the political power of unions?