If you sit down and think about it there is some sense to be made. Bush turned out to be far from conservative, he was a liberal spender and a moderate on many social issues. There was the opportunity to address illegal immigration, nothing was done. Abortion is a landmine of an issue for many, he wasn't exactly a hawk on that issue. There are some issues where he was more conservative but certainly not enough to be considered conservative, if anything he was fairly moderate.
McCain was moderate.
So our last two candidates were moderate republicans and look how they both worked out. Maybe we do need a true conservative?