The Times has this blog post about social security mentioning Citizens United.

The AARP has long fought for campaign finance limits, in part because businesses oppose payroll taxes.  Thus, the recent Supreme Court rejection of government bans on corporate spending in elections was another notable change in the political landscape.

With slower growth of the retired population, politically active youth and businesses freer to spend cash on campaigns, it is actually credible that businesses and young people might inflict noticeable political damage on a candidate who aims to pay for retirements with higher taxes, and help defend a candidate who considers Social Security or Medicare benefit cuts.