“When I work on a bipartisan basis I work with a majority of the Republicans, too,” he said.

Other Republican members on Finance are rankled by claims that they need DeMint on the panel to enforce conservative principles.

Hatch said Grassley, “like any ranking member, wants to make his committee work and there are going to be times to get anything done you’re going to have to work with the majority. … This is a place where compromise is part of the process.”

“Grassley is a very rock-ribbed conservative, let me tell you,” said Hatch, who added that McConnell should base the Finance appointment on seniority or perhaps face rancor within the GOP conference.

One Republican senator said a conservative such as DeMint would “definitely” have an impact on Finance, even if he would join the panel as its most junior member.

“We want to make sure we have solid fiscal conservatives, not just from my perspective, but on the Appropriations and Finance committees,” said the senator, who declined to speak on the record for fear of angering his centrist-leaning colleagues. “It would be very helpful to get those strong on tax and spending policy on the committee.”

Conservatives who want to see DeMint or another conservative firebrand on Finance say it could give Grassley leverage in negotiations with Democrats. They say Grassley could decline some proposals as unacceptable to the most conservative members of his committee.

 “We’ve seen on the Republican side a tendency to go along and obligate taxpayers for too much,” said Rep. Jeff Flake (R-Ariz.), an outspoken House conservative, in reference to GOP members of Finance who have worked with Democrats. “DeMint would help equalize the equation.”