I respectfully demur.
The underlying premise of this position is that pagans have no access to the basic ethical tenets that we believers share, and further, that these ethical norms derive solely from the Bible. To examine this position I will build upon David VanDrunen's argument in A Biblical Case for Natural Law (which I will not actually cite since I can't find my copy).
In Genesis 20 we read of Abraham journeying to Gerar. Fearing that his own life will be taken by the people of this pagan land on account of his wife Sarah's beauty, he lies to them and claims that she is his sister. This backfires, however, emboldening King Abimelech to take Sarah as his own wife. God immediately speaks to the king in a dream and informs him that Sarah is in fact Abraham's wife, and not his sister as he had claimed.
This is where the story gets interesting.
The next morning King Abimelech confronts Abraham and demands an explanation as to why he "brought on me and my kingdom a great sin." The patriarch's defense was the following: "I did it because I thought, 'There is no fear of God in this place.'" In other words, Abraham assumed that since he was in a pagan land with no relationship to the God of Israel or access to divine revelation that it must be the case that these people are unfamiliar with the fact that it is wrong to take another man's wife.
Some things to note in this account are: (1) Abraham's assumption was clearly false; (2) The "fear of God" did exist in the land of Gerar; and (3) King Abimelech recognized a "great sin" as some-thing "not to be done" and rebuked Abraham for almost causing him to fall into it.
Returning to the issue of the upcoming election, then, I would submit that the believer need have no fear that electing a non-Christian will immediately result in widespread immorality and rampant perversion. Natural law is a biblical doctrine, and the works of God's law are written on the hearts of all men.
Even (gasp!) Barack Obama.