State Senator Brad Zaun won a crowded primary in Iowa’s third Congressional district in 2010, and he has led the only public polls in IA-03 this spring, but my best guess is that Iowa Renewable Fuels Association Executive Director Monte Shaw will end up becoming Staci Appel’s competition in the general election campaign. I assume no candidate will win 35 percent of the vote in tomorrow’s primary, forcing a special district convention to select the nominee. From where I’m sitting, Shaw’s strengths as a candidate outweigh his potential weaknesses with Republican voters and delegates.