DES MOINES — With the Iowa legislature moving toward adjournment, the year-long battle to overturn the Iowa Supreme Court decision establishing same-sex marriage is moving to a new venue — the campaign trail. Party leaders insist the 2010 election will be about the economy, jobs and protecting Iowans’ priorities: education, health-care, safe communities. The effort to overturn the April 3, 2009, decision legalizing same-sex marriage is unlikely to be “the” issue of the campaign, campaign operatives say, but it will be an issue that, in some races, may influence the outcome. “We don’t have to go out of our way...