I’m thinking this is more important than a “Quotes of the Day” post, no? In fact, so jaw-dropping is it, I had to read it twice to make sure I wasn’t misreading it. The site that posted it isn’t partisan either: It’s The Monkey Cage blog at the Washington Post, a “data journalism” hub a la Nate Silver’s FiveThirtyEight that prioritizes insights gleaned from number-crunching above left/right argumentation. In fact, the conclusion to the post isn’t that the study’s results necessarily cast a pall over the integrity of some U.S. elections and even the legitimacy of ObamaCare’s passage. It’s that, among the possible solutions, maybe we should think about allowing non-citizens to vote.

Funny thing: I found myself nodding along this morning to this post by Jim Geraghty in which Jim argued that right-wing accusations of voter fraud committed by Democrats are overblown, a fantasy into which conservatives sometimes retreat to avoid having to grapple with electoral failures. His larger point is still true — massive fraud is very unlikely. But what about just a little bit of fraud in very close races? And what if the fraud occurs not on the back end, with crooked electoral officials stuffing ballots with phony Democratic votes, but on the front end, with non-citizens casting votes for Democrats without even realizing that what they’re doing is illegal?

Our data comes from the Cooperative Congressional Election Study (CCES). Its large number of observations (32,800 in 2008 and 55,400 in 2010) provide sufficient samples of the non-immigrant sub-population, with 339 non-citizen respondents in 2008 and 489 in 2010. For the 2008 CCES, we also attempted to match respondents to voter files so that we could verify whether they actually voted.

How many non-citizens participate in U.S. elections? More than 14 percent of non-citizens in both the 2008 and 2010 samples indicated that they were registered to vote. Furthermore, some of these non-citizens voted. Our best guess, based upon extrapolations from the portion of the sample with a verified vote, is that 6.4 percent of non-citizens voted in 2008 and 2.2 percent of non-citizens voted in 2010.

Because non-citizens tended to favor Democrats (Obama won more than 80 percent of the votes of non-citizens in the 2008 CCES sample), we find that this participation was large enough to plausibly account for Democratic victories in a few close elections. Non-citizen votes could have given Senate Democrats the pivotal 60th vote needed to overcome filibusters in order to pass health-care reform and other Obama administration priorities in the 111th Congress. Sen. Al Franken (D-Minn.) won election in 2008 with a victory margin of 312 votes. Votes cast by just 0.65 percent of Minnesota non-citizens could account for this margin. It is also possible that non-citizen votes were responsible for Obama’s 2008 victory in North Carolina. Obama won the state by 14,177 votes, so a turnout by 5.1 percent of North Carolina’s adult non-citizens would have provided this victory margin.

Obama winning a state illegally in a presidential election is bad but will be dismissed on grounds that it didn’t affect the overall result. Flip North Carolina to McCain’s column and it’s still a giant blowout. Franken winning a Minnesota seat illegally is a different ballgame. He was the 60th vote for ObamaCare. Replace him in the Senate with Norm Coleman and the law probably never passes. The authors are arguing overtly that health-care reform was made possible only by illegal votes. There are a bunch of races this year that could end up with whisper-thin margins of victory as well — Perdue versus Nunn in Georgia, Cassidy versus Landrieu in Louisiana, Tillis versus Hagan in North Carolina, even Gardner versus Udall in Colorado. If Democrats eke out victories in a few of those by a few thousand or even a few hundred votes, why would you believe after reading this study that those victories were fairly earned? And remember, as a Twitter pal points out, the numbers in the study are based on non-citizens who admitted to voting when asked. How many voted and were smart enough not to cop to it?

Read the whole post. One interesting detail: Less educated non-citizens were more likely to vote than well educated ones were. That suggests (but doesn’t prove, natch) that some of this illegal voting is being done out of ignorance. Better educated people know that they’re not allowed to vote and don’t attempt it; less educated ones don’t know, and therefore do. Another detail, an important one, is that voter ID laws seem not to work. Almost three-quarters of non-citizens who voted said they presented photo ID to get their ballot. If you want to stop them from voting, you’ll either have to insist on some sort of citizens-only ID (plenty of blue states issue driver’s licenses to illegals, remember) or come up with a new way to verify voters’ eligibility. There are a few caveats at the end of the post too about why the authors’ findings might be wrong. Expect lots of liberal pushback on this next week attempting to exploit those caveats.

Exit question: Does this about wrap things up for GOP participation in comprehensive immigration reform next year? Border hawks have argued all along that mass legalization of illegals is a ploy by Democrats to fast-track voting by a group of people who, on balance, support left-wing policies. Now here’s a study suggesting that not only is illegal voting by non-citizens already happening, in some key cases it’s actually decisive. How does a House Republican who’s on the fence about amnesty justify voting yes to his conservative constituents after this? And how does Obama justify an executive amnesty to centrists and independents who are skeptical but otherwise undecided?