On first glance, if you read the encomiums to Sen. Tom Coburn, you might assume the retiring Oklahoma Republican was some kind of moderate. National Public Radio described him as an “Obama friend;” the president himself said he was “sad” to see Coburn go.

An Oklahoma Democrat praised Coburn by saying, “I also admire that he stands up for his principles and views even when it means going against more extreme members of his political party."

But Tom Coburn was no Arlen Specter. Coburn, a medical doctor, once said, “I favor the death penalty for abortionists and other people who take life.” He was the only member of Congress to endorse perennial candidate Alan Keyes for president in 2000. Originally elected as part of the 1994 “Republican Revolution,” he was part of a conservative coup attempt against then Speaker Newt Gingrich.

Ahead of the 2008 Republican presidential primaries, this writer heard a Coburn appraisal of Mitt Romney that deviated from the standard conservative Christian critique of the former Massachusetts governor’s Mormonism. Coburn said he found it hard to believe that Romney, as an educated Mormon, could have only recently discovered that abortion was wrong. (Romney switched from pro-choice to pro-life before running for president.)

Despite being friends with the current Democratic president—at this same event, he said, “Barack is a liberal, but he’s a good man”—Coburn was willing to criticize Obama. In fact, he would go so far as to say Obama was risking impeachment.

When Coburn decided to return to Washington as a senator in 2004, the Republican establishment wasn’t happy. As the Washington Examiner’s Tim Carney points out, the entire Senate Republican leadership gave money to Coburn’s primary opponent, Oklahoma City Mayor Kirk Humphreys. So did all the appropriators.

Humphreys received donations and endorsements from big Republican names in Oklahoma too: retiring Sen. Don Nickles, Sen. Jim Inhofe, Rep. J.C. Watts, emerging GOP leader Tom Cole. This was despite there being good reasons to believe Coburn would be a stronger general election candidate. But Coburn won the primary anyway, by an overwhelming 36-point margin.

Coburn would later be christened the Senate’s “Dr. No,” a title he shared with House member Ron Paul, a fellow obstetrician. But for both good and ill, Coburn was a very different lawmaker than Paul.

The Oklahoma senator served on the National Commission on Fiscal Responsibility and Reform. Unlike some of his Republican colleagues, Coburn voted for the Simpson-Bowles recommendations. “This plan will not just avert a disaster, but help drive the kind of economic recovery we need to create jobs and spur growth,” Coburn said in a statement with Idaho Republican Mike Crapo. “The plan’s provisions to lower tax rates while creating fairness in the tax code are similar to pro-growth policies supported by President Reagan.”

Coburn’s Simpson-Bowles advocacy started a mutually nasty and unfortunately counterproductive feud with anti-tax-hike activist Grover Norquist. But when GOP vice presidential candidate Paul Ryan came under fire for his own rejection of Simpson-Bowles, Coburn defended him.

“Paul Ryan doesn’t do things politically, he goes out and leads with his chin,” Coburn said, describing the criticism of Ryan as “nonsense.” Coburn was somewhat more willing than other conservatives to contemplate new revenues in order to win concessions of entitlement spending and long-term debt.

Coburn’s annual “Wastebook” was a quintessentially conservative document that helped journalists expose wasteful and fraudulent federal spending. The $65 million in post-Hurricane Sandy tourism spending has become part of the drumbeat of criticism against New Jersey Gov. Chris Christie. But the document was also in the tradition of the late Wisconsin Democrat William Proxmire’s “Golden Fleece.”

Coburn wasn’t always a fan of symbolic gestures, something that occasionally brought him into conflict with his fellow conservatives. He quarreled with Ted Cruz on anti-Obamacare tactics: "To create the impression that we can actually defund Obamacare, when the only thing we control, and barely, is the House of Representatives, is not intellectually honest." And he stood up to his party’s most reflexive hawks on defense spending, which he was willing to subject to the same scrutiny as social programs.

Tom Coburn’s early departure from Congress is thus sad for two reasons. The man was never likely to stay long: he abided by self-imposed term limits in the House and promised to do so again in the Senate. The fact he is leaving before his term is up suggests he needs to devote more time to his health.

Second, Coburn was trying to be both seriously right-wing and serious about governing. And that is something that will not easily be replaced.

W. James Antle III is editor of the Daily Caller News Foundation and author of the new book Devouring Freedom: Can Big Government Ever Be Stopped?

Image: Flickr/Senate Democrats. CC BY 2.0.