Iowa voters are politically schizophrenic...please explain to me how the same voters elect, and keep on re-electing Grasseley AND Harkin? That's the oddest pair of senators from the same state..
I've long wondered that, too. The only possible explanation I can muster comes from looking at the one area where they vote alike (instead of cancelling out each other's vote): Agricultural Issues. Each senator has amassed a lot of power during his tenure, and I can only guess there are a lot of voters who recognize that and cast their votes based on farm-economy issues.
Another explanation is that 30% of the people who show up to vote are totally clueless about the fact that these two senators are politically polar opposites. I can't buy that. Iowans are both older and smarter than the average nincompoop.