The Des Moines Register:

Republicans view the 26-24 Democratic control of the Senate as a last barrier holding them back from marching ahead on issues from tax cuts to a constitutional amendment to ban same-sex marriage.

Small-business owner Cindy Golding, a Republican, and former television news anchor Liz Mathis, a Democrat, say they’re focusing their campaigns on issues important to the district they seek to represent. But the possibility of a 25-25 Senate split has attracted hundreds of activists from around the state to the district and hundreds of thousands of dollars in campaign spending in an attempt to sway the outcome.

...For Republicans, [Democrat Senate Majority Leader Mike] Gronstal has become a symbol of Democratic roadblocks to their legislative priorities, especially because of his refusal to allow a Senate vote that would pave the way for the public to vote on a constitutional amendment to ban same-sex marriage.

... groups like the National Organization for Marriage, which opposes same-sex marriage, have jumped into the fray. The group sent out fliers advocating for Golding, saying, “The future of Iowa hangs in the balance.”