From what I understand, when voting in the presidential election of the United States, in theory you don't vote for the president. You vote for an elector of the electoral college who then votes for your president. Now, in practice it's the same. I'm wondering however if the electors have ever voted for someone else than they were implicitly supposed to vote for? Has a democrat elector ever voted for a republican? Has an elector ever voted for another candidate than the one campaigning? Could the electors in theory all vote for someone else than the presidents campaigning?
This is a great question. So the best way to answer this is to say that nowadays, electors are almost always 'pledged' -- or committed in advance to vote for a specific candidate.
During the middle of the 20th century in particular, a phenomena of 'unpledged' electors did develop, mostly because of some of the major cultural changes occurring at the time in the south regarding civil rights. I might be wrong here-- but I believe a group of unpledged electors has only ever actually been elected once, and they ended up voting for a different Democratic candidate than the one that the convention put forward as the party's nominee (Kennedy). I may be wrong/not as right as I could be here.
Further-- there's a phenomena called "Faithless" electors who pledge themselves to a candidate, and then vote for 'the other guy' as you call it. I think there's been about 150 cases of this, and about half the states in the country have laws that allow the state's government to prosecute these electors, as they had pledged to support a different candidate, and were chosen on those grounds.
Tl;dr-- Yes, members of the electoral college have voted for 'the other guy' before. They've never impacted an election though.
That happened in the 1960 election.
http://uselectionatlas.org/RESULTS/national.php?year=1960&f=1&off=0&elect=0
15 electors in the then democratic states(now former), in Mississippi and Alabama. Gave their votes to Segregationist Harry F. Byrd and Strom Thurmond. Who weren't even running.
Because before the rules changed you voted for the party of the elector who would then give their votes to their party.
However electors in mississippi and alabama refused to support JFK because at the tail end of the election campaign he moved into supporting civil rights to gain black support.
http://en.wikipedia.org/wiki/Unpledged_elector#Constitutional_background
After 1960's no state and the two parties wanted a repeat so afterwards instead of electing your elector who represented a party who would just give it to somebody else.
The states decided to list the National Candidate of the Party at the election. effectively voiding the possibility of unpledged electors.
Excellent answers, thank you. While we're at it, what is the historical reason behind using an electoral college? I understand why different states have (sometime) in proportional amount of votes. But why through electors?