Chris Christie may continue his Obashing, instead of publicly showing his appreciation for Obama while claiming that he was still "endorsing" Romney. Obama may have won NH by a smaller margin, and Obama may get slightly less than 50% of the popular vote, instead of the 50.4% majority that he is now enjoying.
Besides that, no effect at all. Don't see how things would change much, he would still win Florida since it is totally unaffected, though perhaps it would be within a 0.1% margin, which would automatically trigger recounts and recounts. And so, no effect at all, not even the electoral vote tally would have been changed, though Obama may have won 49.9999999% of the popular vote instead of 50.4%


(Even so, I think Obama would still have won something like 50.1%

)