Tempo94, I could easily see things going either way. Since the court is majority-Democrat, my first instinct would be to say they would support the recent decision striking down the gay marriage ban. However, please keep in mind that Iowa Democrats are NOT necessarily as liberal as those in other areas of the country. By that some token, though, the state has been moving more and more toward recognizing gay rights. Just this year, the governor signed a sexual orientation and gender-identification protection bill for schools in the state.
Really, anything could happen. There is strong movements on both sides, and it will be a battle. This is not the last you'll hear of this, for sure.
I have a sneaking suspicion, though, that the ban will be struck down in kind of a modern-era Brown vs. Board of Ed. case. It's going to be very exciting.