After the 2008 election, the GOP Senate caucus killed all of DeMint's proposed reforms. This was an early spark in the conservative insurgency of 2009 and 2010. DeMint fired up his Senate Conservatives Fund, and immediately took sides against the party leadership -- supporting Pat Toomey against incumbent Arlen Specter in Pennsylvania and Marco Rubio over GOP-anointed Charlie Crist in Florida. It was open warfare, with DeMint, the Club for Growth, and Tea Party groups on one side, against the National Republican Senatorial Committee, Minority Leader Mitch McConnell, and the GOP's K Street kingpins, such as former Majority Leaders Bob Dole and Trent Lott.Worth a read in full.
Conservative, anti-establishment Sen.-elect Rand Paul, R-Ky., knows what he's up against. During his primary race against McConnell's hand-picked candidate Trey Grayson, Paul received a check from only one sitting senator -- the retiring and widely disliked Jim Bunning. Meanwhile, 19 GOP senators -- and plenty of former senators now on K Street -- funded Grayson in the primary.