The seat that's numerically next, across the county in north Ankeny, appears to be the primary battleground for Republicans. I dubbed this one "This Is Where Your District Went," in honor of all the rural House Republicans who got paired up.
Ankeny has grown enough in the past decade that, for the first time, it gets split into two House districts. Old House District 70 was, basically, the city of Ankeny, which with its 2000 population of 27,000 was about 90% of a House seat. By 2010 Ankeny had grown to more than 45,000 and now dominates two House seats.
Incumbent Kevin Koester is in the south Ankeny District 38, a near-even swing seat. Open District 37 has a GOP registration edge of 2368 (as of April; I'll update all those numbers sometime post-caucus. They'll all get more Republican, and the Republicans will act like that means something more than one party having a contested caucus and one not.)
Candidate Jim Robidoux, a middle school Spanish teacher, is kind enough to list five potential primary opponents on his web site:
And that's the larger point here: the convention. State law requires 35 percent in a primary to win a nomination, otherwise it goes to a convention. For legislative seats, the deciders are county central committee members from the precincts in the district. For county offices, it's the county convention delegates. Either way, the deciders are chosen on caucus night. One more reason to stay in your own party's caucus in Polk County (see also House 77 in Johnson County), and to stick around past the "voting" and through the delegate and committee electing.
See, the way GOP caucuses work, there's no direct connection between the "straw vote" count that's reported and the delegates that are elected. You can go to your caucus and "vote" for Mitt or Newt, and then go home. But it's the people who stay behind (mr subliminal says Ron Paul) who elect those delegates and committee members. So in June when your six way primary is indecisive, the votes go to the people who stuck around.