05/17/2010 06:47 pm ET | Updated May 25, 2011

Arlen Specter -- A Political Outlier in a Congress of Lemmings

He has angered me, too.

In my case, it was in 1987, when Arlen Specter was torpedoing the Supreme Court nomination of Robert Bork. I then believed Bork was qualified. At the time, Specter said he had "substantial doubt as to how [Bork] would apply fundamental principles of constitutional law."

I'm not alone. Over the years, Specter has upset just about everybody at one time or another.

Conservatives have been angry about Specter's treatment of Bork, his "not proven" vote in the Clinton impeachment, and his support for stem cell research. Liberals, particularly women, did not appreciate his aggressive cross-examination of Anita Hill during Clarence Thomas' Supreme Court confirmation hearings. More recently, he bucked organized labor by refusing to support card-check legislation. Even conspiracy theorists have gotten hostile, deriding his single-bullet theory in the JFK assassination.

Which is exactly why we need him in the U.S. Senate.

The only talking points Specter has followed his entire political life are his own. Give him credit for being true to his word. When he ran citywide with Tom Gola in 1969, it was on this slogan: "They're tougher. They're younger. And nobody owns them." Well, he's older now, but no less tough and no more controlled than he ever was.

"This guy is a guy with more steel in his backbone than most people have in their whole body," Vice President Biden, who shared three decades worth of Amtrak rides with Specter, told me last week.

I have known Specter for 30 years, since a chance encounter in the 500 level of Veterans Stadium during an Eagles game. At his side that day was his son Shanin, now a close friend.

Specter was in the midst of the campaign that would take him to the Senate. But he had already achieved much by the time of our first meeting. He'd been a hard-charging Philadelphia prosecutor invited to investigate the Kennedy assassination for the Warren Commission, when he authored the single-bullet "conclusion" (as he puts it). He'd battled corrupt magistrates in Philadelphia. He'd been elected district attorney as a Republican in a Democratic stronghold, and had narrowly missed being elected mayor. Statewide, Specter had run and lost for governor, and run and lost for Senate. No one could have predicted he would become Pennsylvania's longest-serving U.S. senator.

The Senate he entered bears little resemblance to today's.

He had company then. There were many Republican senators who shared his pragmatism: Mark Hatfield and Bob Packwood of Oregon, Bob Stafford of Vermont, Lowell Weicker of Connecticut, Bill Cohen of Maine, John Chafee of Rhode Island, Warren Rudman of New Hampshire, Alan Simpson of Wyoming, Jack Danforth of Missouri, Charles Percy of Illinois, Charles Mathias of Maryland, and John Heinz of Pennsylvania.

In his 2000 memoir, Passion for Truth, Specter told a story about a party held at the home of Majority Leader Howard Baker, during which Specter heard Hatfield proudly label himself a liberal.

"That was the first and last time that I heard a Republican senator identify himself as a liberal," Specter wrote. By 1999, the Wednesday Lunch Club, a weekly gathering of moderates founded by New York Sen. Jacob Javits in the 1970s, had only five members.

Today, things are so polarized that you could probably predict the way 95 of the 100 members of the Senate will vote on any given piece of legislation before it is even introduced. But not Specter.

In a world where each polar extreme gets its own cable channel, Specter should be celebrated for his critical thought. Some would depict him as lacking in passion, weak or self-serving. Why? Because no one descriptor seems to sum up his mixed-bag politics: tough on crime, hard on terrorists, supportive of labor, respectful of civil liberties, and moderately liberal on social issues.

It's ironic that Joe Sestak's television ad says Specter switched parties to save one job, his own. Specter's decision to cross party lines and cast one of just three Republican votes for the stimulus last year was the straw that finally broke the elephant's back. Pat Toomey stopped considering a gubernatorial run, switching gears for a rematch with Specter. Conservatives began mobilizing behind Toomey. No matter how effective you believe the stimulus to be, it's clear that Specter imperiled his already shaky bona fides among GOP primary voters to do what he thought was best to keep this country from going into an economic ditch.

It is that record of independence and never-ending unpredictability that makes Specter an outlier in the Senate. The irascibility many have experienced firsthand makes him irreplaceable.