While voter fraud does occur, it is not done by individual voters (or at any rate when they do the effect is minuscule).  The real frauds occur while the ballots are being counted.

That being the case, one has to wonder at the motivations of people who want to impose rules keeping the poor and similar people from being able to vote.  Remember voting is a fundamental right, and cannot (or at least should not) ever be taken away.  The motives, however, are fairly obvious -- to give the racist, xenophobic political party an advantage.  Such things are undemocratic and those who push for them are hypocrites.