Ah, well there we have the fallacy, that the GOP is a conservative party. It is not. It merely has the support of conservatives because it is far and away the lesser of evils, and at least has some prospect for conservatives to advance our priorities, while our other choice leaves us with no prospects at all.
Oh, I see. Yes, I've been using "conservative" here as if it were interchangeable with the Republican Party as a whole (the leadership and its policies in particular). You are correct to have corrected me. :)
Regardless of the reason it has such support (even if only temporary), it is that support that makes the GOP a conservative party. I suggest dictionary for determining what is or is not, conservative.