Illinois' Democratic Senate primary will test if the party's base wants a more confrontational approach against the GOP. The race pits Lt. Gov. Juliana Stratton against Rep. Raja Krishnamoorthi, with immigration policy as a key dividing issue. Democrats clamoring for their party to get tougher on President Donald Trump will get a sense of how much of it their base wants when voters in deep-blue Illinois select a Democratic nominee to replace retiring incumbent Sen. Dick Durbin. Unlike the recent Senate primary in Texas, where Democrats publicly weighed questions of electability, the Praire State's March 17 primary is focused on...