Do Non-Citizens Voting Illegally Affect Election Outcomes?

Political Science professors Jesse Richman and David Earnest, in the Washington Post:

In a forthcoming article in the journal Electoral Studies, we bring real data from big social science survey datasets to bear on the question of whether, to what extent, and for whom non-citizens vote in U.S. elections. Most non-citizens do not register, let alone vote. But enough do that their participation can change the outcome of close races....

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.

Why would the possible affect on one or two elections matter?:

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.

Guess what: Voter ID would not solve this problem, if a problem it is.