Republicans are again proposing a change in the Iowa Constitution to ban gay marriage. Rep. Dwayne Alons of Hull introduced a joint resolution Tuesday signed by 34 other House Republicans. Senate Republicans filed an identical bill last week. The measure would begin the process of amending the state constitution to permit marriage only between a man and a woman. The resolution would need to be passed by lawmakers, then approved by the Legislature elected in 2014 before going before voters.