Hm. Let me play devil's advocate...
Where do rights come from? Before anyone presupposes that rights exist (When they are concepts that reflect not on states in nature but on mindsets of people who share them), how can we determine that the collective choice of democracy is indeed the endresult and right result?
Let me put it this way- When one has might and uses it to rule (And uses it to maintain said rule), that's not a right to rule, it's a fact. That IS rule so long as it goes on. Now, let's replace might with "placed by majority". One has the will of the majority behind them to get into power, and that may help one maintain power, but is it really a right in the strictest sense?
Right is defined as "that which is just, morally good, legal, proper, or fitting."
Quite an open-ended word to work with. Let's take it one at a time...
Just is fairness. If the ruler is fair, then he is right in this sense. If he oppresses everyone fairly, he can rule like that and it'd be in a sense right.
Morally good is a subjective term. Why? Because while there are objective moral laws, there are subjective ones as well. Unless the objective morality was realized through reason, supported, and made into established rational fact, it could not be used in this sense. However, there's a multitude of different moral goods according to each and every individual. Depending on the person or situation, the ruler may be right for a second, and wrong for a second. He or she might be right for their entire rule, or wrong, or a mixture of both. This can't be established objectively on many cases- while we could argue that killing a small child is always wrong, banning smoking may be seen as either depending on the party. So how can we objectively determine a ruler to be morally good when the term itself is subjective?
Legal. Hell, the leader IS legal in somuch as they make the rules. In this case, might is clearly right.
Proper? Subjective. Eating with your elbows on the table isn't proper, but I'm sure Bush can still be president if he has bad table manners or speech etiquette.
Fitting? Could we be more vague?
So really, I'd argue that might is right CAN be argued as correct if you look simply at the definition of all the elements involved. Do I believe or feel it's right? No. But from what I've concluded here, it is possible to argue that it is so.