In an interview with Iowa Indy alum Douglas Burns, State Rep. Christopher Rants (R-Sioux City) discouraged State Rep. Rod Roberts (R-Carroll) from running for governor. (Both men are rumored to be mulling a bid, but Rants is probably a lot more serious about it at this point.)  Rants’s argument, as retold by Burns, is that a gubernatorial bid would imperil Roberts’s seat in the Iowa House.

Burns thinks that argument is flat-out wrong, and he points to past election cycles in which Democrats haven’t even fielded a candidate against Roberts. That may be true, but Rants’s claim isn’t completely baseless: On paper, Roberts’s district looks like it should be a top battleground, since it actually has 2,000 more registered Democrats than Republicans. Roberts has coasted to reelection, but a political newcomer might not have the same luck.

That said, concern for one’s state legislative seat probably shouldn’t be the only factor a candidate weighs when he or she decides to seek higher office. If it were, Rants might not be running either.

Though the former speaker has been reelected many times, it hasn’t always been a cakewalk. The GOP does hold a slight registration advantage in his Sioux City district, but not enough of one to prevent Democrats from nominating candidates and spending a few bucks there each campaign cycle. Without an incumbent, depending on political winds and the resources available to both sides, the GOP could certainly lose Rants’s seat, too.

Even if both seats are likely remain in the Republican column after November 2010, without incumbents running, the House GOP will have to divert resources away from potential pickup opportunities just to play defense. The impact may not be huge, but statehouse races have turned on less.