[TPM SLIDESHOW: Meet The 2012 GOPers: Ex-Gov. Tim Pawlenty (R-MN)]
Means-testing of Social Security is politically tough, because it would have the effect of -- dare we say it -- redistributing wealth. For illustrative purposes, if this idea were taken to its absolute extreme and the whole program was means-tested (which Pawlenty is expressly not proposing here), this would transform it from a universally-enjoyed entitlement to a social welfare program.
But even means-testing the cost-of-living adjustment would have a partial effect in this direction, by cutting an expected increase in benefits for wealthy people, and be vulnerable to political attacks from the right.
On the more conservative side, Pawlenty also says that raising the retirement age should be an option: "Your retirement age is going to be pegged to some reasonable correlation to life expectancy."