States are nailing down dates to release 2015 premium costs under ObamaCare, and their decisions will guarantee a drumbeat of news about rate hikes all the way to the November midterm elections. Democrats are bracing for grim headlines that could put the unpopular law back at the forefront of voters’ minds. Premiums are expected to go up in a majority of states, as they do every year, but the size of the increases could go a long way toward determining how much political damage Obama-Care inflicts on vulnerable Democratic lawmakers. A survey by The Hill of state insurance commissioners found...