There is no way to disaggregate all the hundreds of factors that went into the 2012 election. So we'll probably never be able to say "X% of Obama's victory cam

There is no way to disaggregate all the hundreds of factors that went into the 2012 election. So we'll probably never be able to say "X% of Obama's victory came from data mining and Y% came from hiring an addition Z Field Organizers". But given the disadvantages Obama had going in, he definitely performed towards the top-end of what could be expected.