I am sure Russia wouldn't mind having it go away, as it is one less foreign policy headache to deal with. Obama may or may not be weak on foreign policy, but saying he will be more flexible after the election gives off the view that he would be more willing to give into Russia's demands once he does not have to worry about his own political hide.
It is a rather frail possibility after the attempted revolution and the failure that brought about. Not to mention the Iranian populous remaining quiet during the Arab Spring.
You seem to also forget that Georgia was not even engaging in fighting in Russian territory during this, they were fighting with a breakaway Provence and Russia decided it was time to bring Georgia to it's knees.
And the missile shield was never meant to target Russia, it was there to target Iran, but here is the thing Russia and Iran are good buddies especially when it comes to oil. You cannot tell me there is not some back channel pressure from Iran to Russia to make this shield go away.