Isn’t it strange how the primaries are set up to make the least electable candidate the party nominee? The winner of the primary is usually one of the extremists, on the left-right map, as the extreme liberals and conservatives are generally the ones that show up at the primary polls.
However, in the final election, the extremists don’t do as well. The Democratic candidate (even if a moderate like Joe Lieberman) is already going to pull 95% of the extreme liberal vote, and the Republican candidate (even if a moderate like Colin Powell) is going to pull 95% of the conservative vote. A centrist candidate just isn’t going to make it through the primaries very easily.
And that, my friends, is why we are choosing between the proverbial giant douche and turd sandwich. [Apologies in advance for the pop culture reference that will probably soon be worn out.]
It’s not so much that the primaries are set up to favor the extreme wings of either party – it’s that people with extreme beliefs tend to be more motivated to turn out and vote in the primaries than people without strong opinions.
In the final election, the extreme wings of both parties tend to cancel each other out – especially because they won’t exactly be changing allegiances to vote for the other side – so the candidates attempt to swing the moderate voters to their side. Of course, they have to do it in such a way as to not dispirit the extreme wings to the extent that they stay home.
It’s just like the economic models about two competing businesses locating right across the street from one another (sorry, but it’s been a LONG time since I took microeconomics, and I can’t remember the name of it). It would seem that, if you were to imagine two competitors, and all customers on a line, they would locate about 1/3 from either end. However, they always end up at the center. If either moves away from the center (i.e. toward the extreme side), it is in the interest of the other to move over and capture the territory that was vacated, because those at his end of the line (e.g. the extreme wing of his base) are no closer to the competition, even if they are further from him.
In the primaries, this effect still holds, but the population that the candidates are competing for is just skewed to the extreme side (this is why most of the Dem candidates went left to try to peel off nutty Deaniacs).