Maine Senator Olympia Snowe stunned the political world yesterday by announcing that she would not seek re-election this fall, despite a significant fundraising advantage and never receiving less than 60 percent of the vote in any Senate race. Snowe’s decision opens a huge opportunity for Democrats to pick up a seat in a blue-ish state. 

In her announcement, Snowe—a noted moderate—cited the “partisanship of recent years in the Senate” to explain why she was suddenly throwing in the towel. Given that her staff didn’t even know about her retirement until the day she announced it, I have a hunch there’s something else at play here, but that’s neither here nor there—the loss of a moderate, who blames nasty partisanship for her demise, is catnip for much of the Beltway press. Many of them stick rigidly to the doctrine of false balance, in which both sides of the political spectrum are always equally to blame for… everything, and that includes the recent gridlock in Congress. Snowe’s retirement has given them a great opportunity to wisely tut-tut about how broken Washington has become, and say that everyone just needs to get along.

Politico’s Jonathan Allen published a piece that epitomizes this genre today. The article, “The center crumbles,” laments that “Congress can’t find the middle ground because no one’s willing and able to stand there anymore."

For some like Snowe, the question is, why bother? The prospect of running hard to win another term—particularly a six-year Senate term—is less and less attractive for folks who came to Washington to make things happen only to find out there’s no common ground to get things done, only partisan point-scoring that leads to paralyzed politics.…

But it’s harder and harder for members of Congress to get along in their own caucuses, to prevent or win primary challenges and to excite their party base in general elections if they find too much in common with the other side.

What Allen’s piece, and many similar analyses, fail to point out is that only one political party has become more extreme and more partisan in recent years: the GOP. Political science professor Keith Poole conducted a comprehensive study that plotted every Congressional vote from 1879 to 2011 along ideological axes, and found that around 1980, Republicans veered sharply right, with no corresponding leftward shift from Democrats. In 2011, the partisan Republican (the “90 percent” Republican) is almost at the limit of conservative ideology, while the partisan Democrat is much further from the leftward extreme—and has barely shifted in the past thirty years. This analysis shows what we can see to be anecdotally true every day: while the Republicans are lockstep behind privatizing Medicare, there isn’t even close to Democratic consensus that Medicare should be extended to everyone.

Snowe’s record clearly reveals a senator fighting battles against Republican extremism. Here are the main reasons she’s known as a moderate: in 2001, she forced Republicans to trim George W. Bush’s tax cut package from $1.7 trillion to $1.35 trillion. She was one of only three Republicans in the Senate to vote for the stimulus plan in 2009, and one of three to vote for the Dodd-Frank financial reform bill in 2010. She supported the “don’t ask, don’t tell” repeal that same year, and earlier in her career refused to vote to impeach Bill Clinton. She also has a long record of pro-choice votes, including recent opposition to the Blunt Amendment on contraception. 

In each of these cases, Snowe was clearly bucking the Republican Party’s social and pro-corporate extremism. But Allen doesn’t explicitly note that. Instead, he provides a Democratic counter-example: that many conservative Blue Dog Democrats lost their seats in the midterm elections. He adds, “Even the big stuff Democrats and Republicans swear they want to do—cutting the deficit, reforming Social Security and Medicare—forget it.”

You might note that “reforming” Social Security and Medicare are generally goals held by right and driven by business-friendly agendas. When it comes to so-called “centrist” Democrats as defined by the Beltway press, it’s almost always people who share those goals. The Blue Dogs are motivated mainly by a pro-corporate agenda, as they oppose regulation and favor lower taxes and small government programs. (Ari Berman details the pro-corporate nature of many “centrist” Democrats here).

Take, for example, another senator who retired recently—this time a Democrat—and blamed partisanship. Indiana Senator Evan Bayh declared, upon announcing his retirement last year, that there was “too much partisanship and not enough progress, too much narrow ideology and not enough practical problem-solving” in Congress. Bayh’s post-retirement plans included the possibility that he might teach at a university, help a charity or “cure a disease, or do something else worthwhile for society.”

He’s since taken a heck of a detour to those noble goals. Within months of retirement from the Senate, Bayh joined a private equity firm, Apollo Global Management, along with McGuire Woods LLP, a powerful Washington lobbying group that engages on climate change and financial sector issues for “well-heeled” clients. He then agreed to help the US Chamber of Commerce in a public anti-regulatory push against, among other things, the Environmental Protection Agency, the Securities and Exchange Commission and the new Consumer Financial Protection Bureau. (For good measure, he also signed a contract with Fox News to provide commentary).

When Republicans are deemed moderate by the Beltway press, it’s generally because they buck Republican extremism, much of which ultimately serves corporate interests. Democrats are characterized as moderates when they hew close to the corporate agenda. You’ll notice a common denominator here—big money and business interests are skewing the democratic process. Washington is indeed broken, and it won’t be solved by Republicans and Democrats sitting next to each other at the State of the Union address.

UPDATE: Rachel Maddow did a terrific segment on this last night, pointing out that not only has Congress moved right in recent decades, but so too has the presidency and the Supreme Court. 

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Also, speaking of ulterior motivations for Snowe to drop her re-election bid, the Sunlight Foundation wonders whether a lawsuit targeting Snowe’s husband’s involvement in a for-profit education company might have scared her out of the race.