Voting is a tricky thing, since it’s a positive, or government-created right; you don’t have a right to vote in the state of nature. The social contract creates voting.Negatives who are running the social contract analysis need to frame the distinction between natural rights and positive rights; it's essential to establishing the government's warrant for taking away the right to vote when a felon is convicted.
By entering into society, you surrender a distinctly limited number of your natural rights, for instance the right to extract restitution forcibly from those who have wronged you. In compensation for giving these up, the state gives you some other rights (like voting, and trial by jury). All the other rights not clearly mentioned in the deal are yours to keep, at least in theory. And there’s no sense in saying you’ve given up more than you really have.
I like Kuznicki's answer to the objection that the social contract is a mere construct (call this the "I didn't sign any social contract" objection). Kuznicki writes,
The real question is not whether there was a discrete moment in which you entered into society. Clearly there was no such moment.Later on, in the comments, we get a social contract-esque defense of democracy.
We tell ourselves the story of the social contract as a way of comparing real life to a situation that is obviously just. The more that real-life outcomes approximate the obviously just situation of the social contract, the more confident we can be in the justice of the actual situation. Likewise, the less they resemble an obviously just case, the more we can doubt their justice. Thus, although you never entered into society as you would enter into a contract, we still evaluate society as if you did — and when we find things that you would never accept in a contract, there is a plausible case to be made that these things are unjust.
I see the greatest value to democracy as follows: It ensures, better than any other system we know, a peaceful and orderly transition of power. Peace and order are still worth keeping, even if I disagree with the policies of the candidates running.Kuznicki calls this "lukewarm." Still, from a realistic perspective, lukewarm might be the hottest water we can get.
Added: Oh, and if you need them, here are Kuznicki's bona fides.