Latest at Campaignfreedom.org:

“Since the Citizens United and SpeechNow decisions,
politicians and political parties have struggled under self-imposed
campaign finance laws that once gave them total dominance over the
political sphere.  Although lauded as anti-corruption measures, strict
campaign finance laws mainly prevented political insurgents from gaining
enough of a voice to seriously challenge incumbents.

Without a corruption nexus and with their newly restored
constitutional protections, outside groups have become significant
political players and serious rivals to the traditional party
establishment.  As a result, politicians and political parties are in
the process of dismantling many of the regulations that they once used
to achieve their dominance.

One such restriction is a limit on aggregate contributions. 
Currently set at $117,000 per election cycle, the limit is facing two
Supreme Court challenges.”