Perhaps what you say is true for people who supported Romney at this point in 2008. I was supporting Michelle Bachmann prior to the first caucus in 2008.
By the time I was participating in the Washington State caucus the only candidates still running were Mitt, Ron Paul and Rick Santorum. The exercise was somewhat meaningless at that point, it was obvious to anyone looking at the race that Mitt had the nomination in hand at that point.
I voted for Mitt in the general election, and have regretted it less and less as the disaster of the Obama second term has unfolded. People who abstained from voting from Romney are the ones who should feel bad, in my opinion.
If you voted for Mitt, the odds are that Cruz will never reach his level of liberalism. Thus my statement holds true.
I don’t see how having helped give the GOP permission to be liberal is being washed away by your conscience so easily with time. It should be grating on you because it’s the same lesser evils giving Barry all his power.