I grew up in Bedford, New Hampshire, an extremely Republican town of about 23,000 people that hadn’t elected a Democrat to state office since before World War II. That is, until earlier this month, when my middle school guidance counselor won her very first political campaign. Sue Mullen, 62, bested six Republicans, five other Democrats, and one libertarian to become one of Bedford’s 6½ (it’s complicated) representatives in the state House.