Well, good luck with that, pal (Branstad).
The issue is that the entire delegation is already owned by the lunatic fringe. And that's not just in Iowa, it's nationwide.
Governor Branstad, maybe you remember the Moral Majority and the Christian Coalition. Jerry Falwell, Pat Robertson, and their ilk. It's all an extension of principles from a guy named Rushdoony, to take over the country for Jesus. They ran their people in GOP precincts all over the country. And in the decades since the 70's they became the Republican Party.
Since 2009, there is another faction which got their mealy fingers into the GOP pie, the teahadists. Of course, they are also substantially evangelical, but unfortunately they're also racists.
These two factions own the GOP from the precincts to the national delegations. So good luck with your goal. It took decades for the lunatic fringe to get where they are today. I imagine that it will take a good part of that time for anybody to turn that around.
You don't happen to have a national Branstad church, do you? Remember all those voter guides?
I didn't think so. Too bad for your plan, then.