Super PACs have given GOP megadonors new avenues to make campaign contributions at a faster clip than ever, but in at least one quarter of the party establishment, they may be causing some heartburn this week.

Sen. Jim DeMint's decision to funnel $500,000 to the Club for Growth, disclosed in campaign finance reports filed with the Federal Election Commission this week, represents a deliberate snub of the National Republican Senatorial Committee and an indication of the potential for super PACs to erode the power of the established political parties. 

"Senator DeMint donated money to the Club for Growth because, unlike the NRSC, the Club only backs fiscal conservatives," said Matt Hoskins, a spokesman for the South Carolina Republican. "DeMint wants to help nominate conservatives in key Republican primaries and the Club for Growth was the best organization to make that happen."

Prior to the last campaign cycle, the only avenue for elected officials with excess campaign funds to make large contributions was the political party committees. But changes in campaign finance law triggered by a series of court decisions beginning in January 2010 have given mavericks like the conservative DeMint other options.

"The door was opened for this by Citizens United," said Hoskins, referring to the landmark 2010 Supreme Court ruling that, along with a subsequent lower court decision in a case called SpeechNow, paved the way for the creation of independent committees able to accept and donate campaign contributions in unlimited amounts. 

DeMint's contribution went to the Club for Growth Action, a super PAC operated by the feisty organization of fiscal conservatives that targets politicians it deems RINOs — Republicans in Name Only.

Hoskins said DeMint gave the money to help four Republican Senate candidates he has endorsed: Ted Cruz in Texas, Josh Mandel in Ohio, Don Stenberg in Nebraska and Mark Neumann in Wisconsin. Mandel easily won his state's primary earlier this month to face incumbent Democrat Sherrod Brown in November, but Stenberg, Neumann and Cruz all face competitive primaries against candidates more favored by the party establishment. 

But because DeMint's money is not earmarked, it arguably can help fuel the Club for Growth in its efforts to oust two of his GOP Senate colleagues: Orrin Hatch of Utah and Richard Lugar of Indiana.  DeMint last year pledged not to target any of his colleagues, and Hoskins insists he hasn't violated that promise. He said DeMint has "not supported or opposed" any of his colleagues.

Far from representing a mutiny, DeMint's donations to the Club for Growth shows his devotion to his party's advancement, Hoskins argued. "It shows how committed he is to winning a majority," he said. "But it also shows how committed he is to electing fiscal conservatives. He doesn't want to elect just anybody."