I'm not sure...not sure what the demographics are in Wisconsin. If the majority of Wisconsin voters normally vote GOP, and some of the Dems like Edwards as well, I think it's possible...especially if there were some good local races to get a fairly good turnout.
Where I live, there was nothing but the Pres. primarys. I don't know if that all helps explain it or not?
There were 3 "big" local elections in Wisconsin yesterday, Milwaukee mayor (non-partisan), Milwaukee County Executive (also non-partisan), and a referendum on expanded gambling in Dane County (Madison - that's a story that really should get its own thread, but I'll touch on it when I get there). First, I'll take the mayor's race. There were 9 candidates, but only 3 that really mattered; Tom Barrett (a RAT ex-Congresscritter who thought he would be governor and thus redistricted himself out of his seat), Marvin Pratt (a liberal Common Coucil president/acting mayor - the latter is because John Norquist skipped town a few months early - who saw 3 of his 16 fellow aldercritters convicted on various federal corruption charges and is rumored to be a target of a federal probe), and David Clarke (a conservative sheriff who was appointed to the job early in 2002 and had won re-election as an unregistered Democrat - that's a long story on how he never joined their party but managed to hijack it anyway - in a partisan election later that year). Everyone assumed the race was between Barrett and Clarke, and the two campaigns went after each other. Meanwhile, Pratt took a page from Russ Feingold's 1992 Senate campaign, presented himself as a nice guy, and finished first with 38%, while Barrett also moved on with 32.6% (giving the liberals a commanding majority), Clarke disappointed with 17.1%, and the rest of the field managed 12.3% between them.
Contrast that with the 3-man Milwaukee County Executive race. Scott Walker, who was a Republican state legislator before sweeping into the seat to replace the disgraced and deposed Tom Ament, took 58.7% of the vote in the county, swept all but one of the suburbs, and at last check was leading in the city of Milwaukee while running on much the same platform as Clarke. His main challenger, David Riemer, a "card-carrying Democrat" (quote from him from this morning's paper; make a note of it because this is the first and will be the last time his party affiliation is mentioned, while Walker's is constantly mentioned by that same paper), trying to run away from a record of massive tax and fee hikes while he served as Milwaukee's budget director, only managed 36.2% of the vote and actually lost Milwaukee.
Finally, we have the casino referrendum. Unlike the rest of the state, when Jim (Craps) Doyle signed perpetual gambling expansion contracts with the Indians, he gave the voters of Dane County (not-so-coincidentally where he's from, and where the capital is) a voice on whether they wanted the Indian bingo hall there to expand into casino games. Despite being massively outspent by the tribe in question (at one point, the money was 17,000-1 in favor of the tribe), it went down in flames by a 64.5-35.5 margin.
The 355,000 or so that voted in these 2 (I know, I said 3 above, but just about everyone that voted in the mayor's race also voted in the county exec's race) accounted for nearly 36% of those that voted in the Presidential primaries (the Libertarians also had a contested primary that drew a total of 3,000 voters). Two more things to note; first, Wisconsin has a "semi-open" primary (anyone can vote in any one, and only one, party's primary - indeed, only the voter and the machine know whose primary one voted in because there is no such thing as party registration or separate pieces of paper for each primary), and since the only partisan primary was the Presidential, there were a lot of crossover votes. Second, while President Bush was completely unopposed in the Republican primary, his 158,000+ votes (825,000 or so voted in the RAT primary) were more than Howard Dean got.