Senator Al Franken likely owes his Senate victory to felons. With a razor thin victory over Senator Norm Coleman in 2008 of just 312 votes, felons convicted of crimes such as murder, rape, robbery, and aggravated assaults may have given Democrats the filibuster proof sixtieth vote that allowed Obamacare to be passed.  Americans have good reason to ask how this could happen. Consider this:

--A conservative watchdog group Minnesota Majority has gone through voting records reportedly finding that at least 341 convicted felons voted illegally in just two of Minnesota's 87 counties during the 2008 general election.  Undoubtedly other felons voted illegally in other counties.

-- After culling through 500 initial allegations of felons illegally voting, the Ramsey County Attorney's Office told The Minneapolis Star Tribune Monday that they are seriously investigating about 180 cases.  Another 28 felons have already been charged. Hennepin county, which includes Minneapolis, winnowed 451 initial cases down to 216 that they are still looking at.  Some other felons have already been charged.  Both the Ramsey and Hennepin county attorneys are Democrats.

Whether one believes that those two counties account for 341 or possibly well over 400 felons illegally voting, the 2008 Senate vote was so close and research finds that felons vote so overwhelmingly for Democrats that the odds are quite likely that felons from those two counties gave Al Franken the election.

Even if no other felons voted in any other county, 341 votes and 96 percent of felons voting for Democrats would have given Franken the election.  In fact, more than 96 percent of felons probably vote for Democrats (see here).

How can so many felons break Minnesota's law and vote?  The problem is that voter registration lists are a mess.  States are mandated under Section 8 of the "Motor Voter" law to periodically purge voter rolls -- to remove dead people, felons, illegal voters and those who have moved out of state.

But many states, including Minnesota, have refused to check these rolls, making it easy for felons to vote and for other vote fraud to occur.

The Bush administration had tried to force states to address these concerns.  In 2005, one-third of Missouri counties refused to purge voter roles, leaving more registered voters than voting age residents.

The Democratic Secretary of State Robin Carnahan refused to enforce the federal law, and the Bush administration sued. Yet, in March 2009, the Obama administration dropped the case and it has not brought any others.

Worse, there is some evidence that the Obama administration doesn't want to stop voter fraud. J. Christian Adams, a former career Justice Department lawyer, told the U.S. Commission on Civil Rights last week that Obama's Deputy Assistant Attorney General Julie Fernandes ordered Justice Department lawyers to drop all these cases.  According to Adams, on November 30 last year Fernandes told 40 Justice Department lawyers: "We're not interested in those kind of cases. What do they have to do with helping increase minority access and turnout? We want to increase access to the ballot, not limit it."

For those who claim that vote fraud isn't a problem, Al Franken's election to the Senate demonstrates not only that vote fraud exists but also that it can alter elections and indeed the laws of the country.

Murderers, rapists, and robbers may not be the people we want providing the crucial votes that determine what America's laws should be.

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 book's third edition was published in May.

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