Signing a secession petition is a complete cop-out.
You are right that the best reasons to exit the USA have nothing to do with the individual candidates and everything to do with the nature of Federal abuse of power.
There are 2 courses which might be effective:
1. You begin to actively work/campaign for the education of the people and the election of representatives who will advance your view of the correct limits of Federal power. Keep in mind that many candidates will be imperfect but still worthwhile; we did not get to where we are in 1 step, and we will not return from it in 1 step either. Baby steps must be acceptable, especially early on. This is the work of generations, as it took generations to get to where we are. You will need to be patient and diligent - and both qualities are rare in humans. In time, the USA will begin to resemble the ideas we suppose to claim, but the path will be long, difficult, and messy, as people unlearn their domestication and become, once again, wild and free.
2. Carve out a piece of property - preferably on a national border or ocean. Define a government for yourself and those with you, and defend it with such skills and weapons as you have. This will be the all-consuming work of a lifetime, quite possibly in a shack in the woods in Montana.
A petition to Obama to "Let My People Go" is the act of a crybaby, because it puts the work of implementing either option to other people who have no interest in seeing it through. Note that every state - yes, even Texas - which has sufficient signers has seen their Governor come forward and denounce the notion. The real task of secession and new independence is immense, and no person in power who you might Petition wishes to pursue it. They have far too much investment in the way things are.
Therefore, you will do it yourself or you will not see it.
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As a point of deeper personal editorial, if you agree with the above and see sense in it, you had no reason to vote for anyone but Romney for president. He was far from perfect, but he had a legitimate shot and would begin walking back some of the worst excesses. Ron Paul has some nice ideas, for example, but one does not go directly from starvation to feast; indeed, attempting to do so would bring the worst strawmen of the opposition to life. Romney was not the man to take us back to the way things should be, but he could have been the man to start. Barack Obama is certainly headed for more federal power, not less. This is plain. Those who cannot hold their nose, in politics, are doomed to suffocate.