I saw a video posted on youtube by the ABC a while back talking about voting fraud in Australia which might be relevant to this discussion. Basically they found that the vast majority of reported multiple votes were clerical errors (I assume confusion over people with similar names; possibly people ticking off the wrong person at the polls as well, I don't know) while the small remainder was usually confused older people who generally lived in nursing homes and the like - there because of compulsory voting they have mobile polling stations that go to elderly people in unfortunate situations and allow them to vote, and in some cases the family of those people also take them to the polls on polling day because they didn't know that their folks voted early. Voter ID isn't going to solve that problem really: the only solution is either to create some system to link together polling places and early voting centres to make sure that people aren't voting twice but that presents a different problem if someone is accidentally marked off. Now Australia is different to America (the biggest difference is compulsory voting, although they probably are closer than most countries in that Australia has significant advance voting which lots of countries don't have: plus there you can go to any polling place in your constituency to vote rather than one specific one) but I think that the general principles apply - that multiple voting or fraud is a minuscule proportion of total votes, the reported numbers probably are exaggerated because of admin errors and that any remainder is people voting twice accidentally and individuals basically voting twice just because they can rather than orchestrated plans by shadowy organisations to elect. Besides; most races aren't close enough for it to be a factor; and if it is that close then in most countries the courts would end up calling for a revote if it was that close and irregularities (which would include other things like provisional ballots and questions over spoiled votes) could have changed the winner.
No western democracy has a significant issue with voting fraud, despite all the different systems that they have. Besides; voter ID doesn't solve the problem with multiple voting: the people that are doing that have ways of doing that which wouldn't be beaten by photo ID - besides, if there were they groups trying to fiddle an election I'm sure they'd have a way to give their people fake IDs that'd fool poll workers. Although I don't know how voting in America works that well: here you're linked to a single polling station that you must vote at and we don't have early voting so you either vote by post or vote in person on the day: I know that America has early voting as well which complicates things especially if they aren't linked to individual polling places.
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Here's that video that I'm talking about, I found it quite interesting. Again its Australia; but I think that the general principles apply to other democracies.
