Let 100 papers bloom III. The Framingham-based MetroWest Daily News, the flagship and by far the largest (circulation: about 54,000) of Boston Herald publisher Pat Purcell's 100-plus community newspapers, has endorsed Democrat Shannon O'Brien for governor. That, finally, ought to put to rest the conspiracy theories that Purcell had allowed a few of his weeklies to endorse the Green Party's Jill Stein for the sole purpose of hurting O'Brien and helping Republican Mitt Romney.