In Citizens United v FEC, the Supreme Court removed significant limits on money in politics by allowing corporations and labor unions to spend as much as they want on campaigns -through SuperPACs, as long as it is not coordinated with a candidate or party.
This allows them to bypass parties however and become sole benefactors of specific candidates. Since parties traditionally perform this role, there are suspicions that the case may end up leading to the breakup of parties, since the may be irrelevant. Timothy Noah thinks this might be especially true of the Republican Party:
Super PACs have made it so easy for millionaires and billionaires to
spend unlimited sums on behalf of a particular candidate that these
groups are now routinely outspending Republican presidential primary
campaigns. Indeed, to a remarkable extent, these oligarch-controlled
super PACs are the primary campaign. And, while both parties can
create super PACs, so far GOP super PACs are burying their Democratic
counterparts. Of the top ten individuals funding super PACs, only
one—Jeffrey Katzenberg—is a Democrat.
