When the new Senate is sworn in come January, Republicans will hold the majority. But one of the better Republican senators of the past decade won't be there: Tom Coburn.

The Oklahoman was a rarity. He promised to limit himself to two Senate terms and then kept his promise, even though he could have easily won a third.

Coburn was a real citizen lawmaker, a man who was in his mid-40s and had delivered 4,000 babies — like Ron Paul, the congressman with whom he shared the nickname "Dr. No," Coburn was an obstetrician — before seeking his first elected office.

As Andrew Ferguson observed in The Weekly Standard, "Among 'antigovernment' Republicans no less than Leviathan-loving liberals, our political ranks brim over with men and women whose careers began in second grade with their first campaign for hall monitor."

Not so Tom Coburn.

Coburn also stood out for the respect he elicited from the other side of the aisle, to a much greater extent than other standout conservatives like Jesse Helms in the recent past and Ted Cruz today.

We can't chalk this up to what the conservative writer Tom Bethell described as "strange new respect," the liberal adulation that greets conservatives who suddenly adopt liberal positions (though he certainly sparred on occasion with fellow conservatives, most notably Grover Norquist).

Coburn could be friends with Barack Obama, going so far as to assure a closed-door meeting of conservative journalists that the titular head of the Democratic Party was a "liberal but a good man." But he also warned that the president was "perilously close" to impeachment.

Make no mistake, Coburn was a serious right-winger. First elected to the House in the 1994 "Republican revolution," he was part of a small group of congressmen who fought Newt Gingrich from the right.

In 2000, Coburn endorsed Alan Keyes for president. He made anti-abortion statements stronger than anything Todd Akin ever uttered publicly. As senator he has reminded his colleagues, and the occasional Supreme Court nominee, that Congress' powers are limited to Article I, Section 8 of the U.S. Constitution.

That last bit shouldn't be controversial in a constitutional republic, but in today's political climate a belief that the Constitution is an exhaustive list of the federal government's legitimate powers marks one as far right.

So while you can point to Coburn's support for proposals like the centrist Simpson-Bowles plan, and the occasional Democratic praise for "going against more extreme members of his political party," Coburn was no friend of the less conservative members of the Republican establishment.

Look no further than when Coburn ran for his Senate seat in 2004. The Republican leadership and GOP appropriators lined up to give money to his primary opponent, Oklahoma City Mayor Kirk Humphreys.

Some of the biggest names in Oklahoma Republican politics were behind Humphreys, as either endorsers or financial backers: Don Nickles, James Inhofe, J.C. Watts, Tom Cole. Coburn won the primary by 36 points.

"You could say Coburn was Tea Party before the Tea Party," The Washington Examiner's Tim Carney quipped.

Indeed he was. Coburn's annual wastebook, in the tradition of the late Democratic Sen. William Proxmire's "Golden Fleece" awards, tabulated the misuse of taxpayer dollars in an easily digestible format.

Heeding former Reagan budget director David Stockman's advice to go after weak claims and not just weak claimants, Coburn was an outspoken foe of corporate welfare. He also did not fail to scrutinize the military budget, supporting Pentagon audits and pointing out that taxpayers were spending more money for less defense.

This defied the liberal bumper sticker slogan about education having all the money it needed while the military had to hold bake sales, as well as the belief held by some Republicans that one's commitment to national security can be measured in dollars spent.

Like Barry Goldwater and other conservative statesmen before him, it probably won't be long after Coburn's retirement before liberals hold him up as an example of how reasonable conservatives used to be, even if they often savaged him when he actually served.

"Even Barry Goldwater" is how the standard liberal lament begins in such cases. Soon it will be "even Tom Coburn."

The people who should really miss Coburn are those who want an authentic, adult conservatism. The Senate needs such conservatives, never more so now that Tom Coburn won't be there.