Quin Hillyer makes an interesting — and judging by the polls, entirely academic — argument for why South Carolinians should vote for Fred Thompson, even if they prefer Rudy Giuliani or Mitt Romney.

[H]e gives South Carolinians a chance to set out a marker and decapitate the presidential electoral primacy of Iowa and New Hampshire. Think of it this way: In every Republican presidential contest beginning in 1980, South Carolina has chosen the winner… but, and this is a very big “but”… it always has been forced to choose from a field already narrowed by the two smaller, front-running states. In effect, South Carolina was told it could take the Iowa winner or the New Hampshire winner, but nobody else.

But this time could be different. This time South Carolina could drive a stake through the two-headed Dracula once and for all by choosing its own candidate to push to the fore. When New Hampshire saved George H.W. Bush’s candidacy in 1988, he publicly thanked the state a full nine months later when he won the general election, and New Hampshire enjoyed disproportionate influence during his presidency. If South Carolina chooses its own candidate this time, and he goes on to win, November’s final election night could hear that candidate say “Thank you, South Carolina” in front of all the world.

In this case, Fred Thompson is the man whose entire career rests on South Carolina, and he is the only one who would thus owe the state so much. Not only that, but the race is wide open for South Carolinians to lay down just such a marker. After three major contests so far, GOP voters have chosen three different winners in Mike Huckabee, John McCain, and Mitt Romney. Why shouldn’t the Palmetto State make it four for four, especially for somebody who is the closest thing in the race to a native son?

For that reason, if I were a Rudy Giuliani man on Saturday, I would cast a tactical vote for Thompson, thus giving the former New York mayor a clear shot at Florida without a clear front-runner to overcome. I might even do the same if I were a Romney man seeing a Thompson surge in the state, figuring that one more loss by a suddenly shaky McCain or Huckabee in a state in which each was supposed to be strong might knock at least one of them out of the race and out of Romney’s hair. Tactically, it also makes sense for any mainstream conservative to want to give a boost to the most consistent conservative in the race, just to send a message to those who say the old Reagan coalition no longer has relevance. A win for Thompson on Saturday would tell the world that consistency across the full gamut of conservative issues still carries weight at the ballot box.

And demonstrate, once and for all, that Fred Thompson doesn’t take a dump, son, without a plan.

But it’s not going to happen. Most people don’t bother to vote in primaries. Precious few of those who do vote strategically, which is a good thing for a variety of reasons.

The pre-election polls missed Hillary Clinton’s surge in New Hampshire and did not forecast Mitt Romney’s strong win in Michigan, so they’re somewhat suspect. Predicting behavior is much harder than gauging attitude, especially at a point in time when so many are still undecided. Still, they’ve come reasonably close to capturing the order of finish and vote totals.

Here’s what they show for South Carolina, a mere two days out:

It’s a two-man race, trending heavily toward McCain. Thompson is actually losing support:

For Thompson to win, he would need to keep his own supporters from defecting to one of the two contenders and attract most of Romney’s and Giuliani’s supporters. That’s not going to happen.

Were I a Thompson supporter voting in South Carolina (and I’m neither of those things) I’d either vote for Thompson, anyway, for the satisfaction of expressing my wishes or vote for McCain as the next best viable alternative — and to help stop Huckabee. Most likely, the latter.

I’d likely do the same as a Romney or Giuliani supporter. Ultimately, I’d pick among the realistic choices rather than trying to guess the impact my vote would have three states later in the process. There’s not enough certainty to play that game with any confidence.