Non-Citizen Voting Rights

Just exactly how does a non-citizen get to vote in this country?  Evidently, a lot of them cast ballots.

Based on national polling by a consortium of universities, a report by Mr. Richman said 6.4 percent of the estimated 20 million adult noncitizens in the U.S. voted in November. He extrapolated that that percentage would have added 834,381 net votes for Mrs. Clinton, who received about 2.8 million more votes than Mr. Trump.

Of course, according to the Democrats, voter fraud is so insignificant as to be virtually meaningless.  Which is why they don't want to fix the problem.