I'm confused

In Texas, the Republican party is backing a write in candidate in place of Tom Delay, who they could not get off the ballot, instead of a Libertarian who could actually win. In Connecticut, the Republican party is supporting Joe Lieberman's bid as an Independant, against a Republican on the ballot.

The Republicans I know are always telling me why I should vote for their guy, because they are the closest thing to what I think. If that's the case, why are they clearly acting to entrench statists, instead of supporting someone who can win a race who supposedly has similar views to them?

Is it because statists never like Libertarians? In both races, the Republicans may just help a Democrat get elected, and I think they are just fine with that, so long as no third party nutjob tries to rock the boat.