Republican former state Rep. David Corbin of Stratham says he will officially announce Tuesday that he is dropping his bid for governor. Corbin, 30, a political science instructor, told The Union Leader today he will instead run for the District 24 state Senate seat held by six-term Democrat Burt Cohen of New Castle. “In my five years of being active in New Hampshire politics, the one tendency I’ve viewed as destructive in the Republican-conservative movement is the placement of ego over principle,” Corbin said. “Far too often in our primaries, late in the game they become divisive to the detriment...