Santorum is running for re-election and doing anything he thinks we'll help him win election in a Dem state.
I wouldn't say it disqualifies him as a conservative. I would say it indicates desperation to retain his position, evidence he thinks he's in a weakened position in his race.
Enviable conduct? No, but not quite as your outline it to be.
Sorry...Santorum can be my ally,he can be my friend, but in no way anyone who has their finger in the wind as much as him can call himself a conservative.