How did Scott Lee Cohen survive the Illinois Democratic lieutenant governor primary without one prominent party official raising hay about his sordid past? That's a question Democratic operatives and activists are trying to wrap their heads around this week. And a good deal of blame is being cast at House Speaker Michael Madigan, who chairs the Illinois Democratic Party.

As we noted over the weekend, the Sun-Times' Lynn Sweet described Madigan's stewardship of the state party as "awful."  Speaking at a rally for Alexi Giannoulias' Senate campaign on Sunday, Sen. Dick Durbin -- a frequent critic of the state party infrastructure -- said that the speaker needs to have "a much better process in place so that we know the backgrounds of all candidates as they put themselves up to be Democrats." Via Capitol Fax, watch the senator's remarks:

Ald. Ricardo Munoz (22nd Ward), who serves as a state party committeeman for the 4th Congressional District, offered a similar take this afternoon. "You obviously don't want to have a party bullying people on or off a ballot,"  he told us. "But it's the responsibility of a party to vet, factually, the biographies of candidates. In this case, it didn't happen."

This line of criticism certainly has merit. After all, scrutinizing potential candidates is routine in neighboring states.

For instance, a source close to the Michigan Democratic Party told us today that leaders there conduct a "very thorough vetting" of practically every candidate running for legislative or statewide office. This includes opposition research and, if a potentially damaging item surfaces, polling to test out a candidate's negatives. The source added that the party "wouldn't embark on any race without insisting that gets done." If there is cause for concern, the Michigan party officials hold individual conversations with potential candidates and other party leaders are informed before the primary election or the state convention (where candidates are nominated for the lieutenant governor, secretary of state, and attorney general offices).

As we learned in the case of Cohen, the Illinois party doesn't even conduct cursory background checks on statewide candidates, even when they are outspending the opposition by fast sums.

This contrast shouldn't really come as any surprise to local political observers.  Indeed, long before the Cohen incident, Democratic activists have been frustrated with Madigan's operation of the state party.  We'll have more on that issue later in the week.