The angry buzz over “The Reagans” has grown louder and more pointed. “Advertisers will bail on CBS’ anti-Reagan movie,” commentator Pat Buchanan predicted on “The McLaughlin Group” Sunday. Two days later, a conservative media watchdog group announced a boycott call-to-arms. But CBS isn't showing signs of regretting its excursion into political drama. Based on experience, observers say, it probably doesn’t need to. “The bottom line is, the more attention it (the miniseries) gets, the more people are going to watch it,” said television analyst Marc Berman of Media Week Online. That spells opportunity for sponsors and ad dollars for CBS,...