Updated

A new study by the Minnesota Majority found that at least 341 convicted felons in heavily Democratic Minneapolis-St. Paul who voted illegally in the 2008 Senate race. And it looks quite likely that felons gave Franken his narrow Senate victory.

The six month vote recount in the Senate race was a torturous process. The morning after November 4, 2008 election, Senator Norm Coleman lead Al Franken by 725 votes. Correcting for typos cut Coleman’s margin to 215, and a recount by all the counties reduced it further to 192.

Once the state canvassing board had looked into the intent of voters and counted 953 previously rejected absentee ballots, the final total had reversed that count and handed Franken a 312 vote victory.

This should not be a surprise, especially after the results of the Minnesota Majority study. With this small number of votes separating the two candidates even just hundreds of illegal voters can alter the outcome. By any measure, felons overwhelmingly vote for Democrats.

Academic work by Jeff Manza and Marcus Britton of Northwestern University and Christopher Uggen of the University of Minnesota estimated that Bill Clinton pulled 86 percent of the felon vote in 1992 and a whopping 93 percent in 1996.

Obviously, these are average numbers. More heavily Democratic areas such as Minneapolis-St. Paul would very likely have percentages of felons voting for Democrats that are above these rates. If heavily Democratic Minneapolis-St. Paul were just 3 percentage points above the average, than felon voting in just this one county gave Franken his win.

Other evidence suggests that Manza and Britton's study underestimates the rate that felons vote for Democrats. In my own work, I examined a Public Opinion Strategies survey that interviewed 602 adults in Washington State in May 2005.

Of the respondents, 102 were felons who had their voting rights restored, while 500 were non-felons. Even after accounting for other differences that predict how people vote — race, gender, education level, religious habits, employment, age, and county of residence — felons were 36 percent more likely than non-felons, with the same characteristics, to have voted for John Kerry over George W. Bush and 37 percent more likely to be registered Democrats.

African-American and Asian felons in Washington reported that they voted exclusively for Kerry.

While not all felons may be as Democratic as those in Washington State, the survey indicates that the previous estimates understated how frequently felons vote for Democratic Party candidates.

In fact, it looks as if virtually all felons are Democrats. Felons are not just like everyone else. And the fact that felons are even more likely to vote Democratic than previously believed surely guarantees that some Democratic supporters will continue their efforts to get them to the polls.

Once one acknowledges that other felons illegally voted in Minnesota in 2008, it becomes even more certain that Mr. Franken obtained his Senate seat from felons voting for him.

John R. Lott, Jr. is a FoxNews.com contributor. He is an economist and author of "More Guns, Less Crime."(University of Chicago Press, 2010), the third edition of which was published in May.

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