The intraparty war over earmark reform in the GOP is getting personal, with Sen. James Inhofe (Okla.) accusing Sen. Jim DeMint (S.C.) of being for the practice when it was politically advantageous, only to turn his back on it now.

The fight between Inhofe and DeMint highlights the tensions going on within the Republican Party as it struggles to quickly overcome the first major test of the post-election landscape.

DeMint announced Tuesday morning that he will push for a change in internal Conference rules to create a voluntary ban on all earmarks, including authorizations, appropriations and tax cuts. He will make his case during a closed-door GOP meeting next week, he said.

Inhofe has emerged as the chief opponent to DeMint’s anti-earmarking efforts and has quietly been preparing for this fight for months. He said Tuesday that he will deliver a “pretty strong statement” on the Senate floor Monday that will accuse DeMint of favoring earmarks until they fell out of political vogue.

As a House Member running for the Senate in 2004, DeMint “was really pro-earmark. … He ran as a pro-earmarker,” Inhofe said in an interview. Inhofe was chairman of the Environment and Public Works Committee at the time, and he said Tuesday that DeMint pressed him to secure funding for highway projects in his state to help his electoral chances.

While DeMint spokesman Wesley Denton said he could not comment on any conversations the two lawmakers may have had, he argued that the South Carolina conservative has been upfront about his previous earmarking ways. “He’s a recovering earmarker and stopped requesting earmarks after 2006,” Denton said.

A GOP aide whose boss supports the earmark ban bristled at Inhofe’s attacks, pointing out that the Oklahoman, along with much of the GOP Conference, voted for a nearly identical moratorium on the Senate floor in 2008.

Pointing to Inhofe’s repeated charges that anti-earmark fervor is nothing more than politics, the aide questioned his support of the 2008 moratorium. “Is that how he would describe his vote for the exact same earmark moratorium?” the aide asked.

The escalation in the rhetorical fight between DeMint and Inhofe is a rare public display of a much broader fight going on within the Republican Party, particularly in the Senate.

While the House GOP has essentially locked itself into a ban on earmarks, much to the chagrin of many rank-and-file Members, the Senate GOP Conference has not taken such a step.

Thus far, most of the fighting has gone on behind the scenes. For instance, since word of DeMint’s anti-earmark proposal leaked out, Minority Leader Mitch McConnell (Ky.) and other leaders have quietly been contacting their colleagues to gauge support for the ban and raise concerns, particularly with the sweeping definition of what constitutes an earmark.

Meanwhile, Republicans are preparing a series of other policy resolutions aimed at demonstrating the GOP’s commitment to cutting spending and the deficit, including a balanced budget resolution and a resolution on entitlement spending.

DeMint lined up the support of 10 colleagues before announcing his proposal: Sens. Tom Coburn (Okla.), John Ensign (Nev.), Mike Enzi (Wyo.) and National Republican Senatorial Committee Chairman John Cornyn (Texas), as well as Sens.-elect Pat Toomey (Pa.), Marco Rubio (Fla.), Rand Paul (Ky.), Mike Lee (Utah), Ron Johnson (Wis.) and Kelly Ayotte (N.H.).

Republicans said the 10 should provide a solid base of support to secure passage of the proposal, in part because many lawmakers who support earmarking are wary of becoming targets of the tea party movement in the next primary season.

Inhofe argues that Congress has a constitutional role to play in deciding where federal funds should be spent, and he accused anti-earmark crusaders of essentially bullying Republicans into supporting a ban. “They’ve been demagoguing for so long … they probably will get [the votes] because people are so afraid to be honest,” he said.

Even freshmen who were elected with tea party support are not immune from the pressure, Inhofe said, pointing to statements recently made by Paul that he, like McConnell, would support earmarks for his state.

“I’m pretty disappointed that so many of the tea party [candidates] would be intimidated into taking such a bad vote,” Inhofe said.