I wish we could put them in order of preference. They do that in other countries. But then they usually have like 5 parties to pick from.
So I could say, "I'll take the green candidate first. If he has no chance, I want the democrat, and under no circumstance do I want the republican....."

Then if the green guy really doesn't have a chance, my vote will still matter. I think not only would this cause the pres to actually be the guy that the majority wanted, but it would cause people to not be so afraid to vote for the underdog.