I have heard recently that the Constitution Party (whose presidential candidate, Michael Peroutka, I support) is part of the Christian Reconstructionist movement.
According to some things I have read, Reconstructionism is a post-millennialist theology which believes in establishing a theocracy.
I am not certain to what extent the CP is related to Reconstructionism, or to what extent Reconstructionists believe this. As a premillennialist, I don't see worldly power as transforming the earth into Christ's Kingdom.
This is not to say that Reconstructionists and other postmillennialists are not true Christians; there is, in my opinion, too much of an attempt to conflate all incorrect doctrine with what I would call mortal heresy (i.e. doctrine so incorrect that one cannot be a Christian and hold it). But I would be cautious about a worldview that tends toward theocracy.
Of course, many premillennialists are also a little bonkers, as they are overly obsessed with the Rapture and with bringing about the conditions to produce Armageddon. (I say do God's will now and let His plan work out in His Own good time).
In any case, I am still supporting the Constitution Party because (a) nothing on their website suggests that they desire a theocracy at the national level, and currently I am mainly concerned with their national platform (b) if they get to be a political force (like Nader), then whatever problems they have will be made clear, (c) the Constitution Party provides a rallying point for conservatives who are dissatisfied with the GOP; if it turns out to be defective, then said conservatives can split into a more moderate (but still more conservative than the GOP) party later, and (d) as a protest party it can serve as a way to drag the Republicans rightward, whether or not the party becomes a force, and (e) they are not going to win in this election, so if there are any hidden agendas, they won't be able to enact them.