Pen statists: in Pennsylvania's Senate race, both sides are running for the middle.

UNTIL THE MIDDLE of August, when Virginia's Republican Sen. George Allen belched a North African schoolyard insult at a hapless Democratic cameraman, Pennsylvania's U.S. Senate race was the hottest game in town. The social conservative icon Rick Santorum, a soaring star in the GOP, was in the fight of his life against state Treasurer Bob Casey Jr. The Republican is the third-most powerful man in the Senate; the Democrat is the incredibly popular son of a legendary governor.

It's the race that could determine whether Democrats take control of the Senate; not coincidentally, it's easily going to be the most expensive race of the year. At the end of June Santorum had raised $21 million to Casey's $11 million. (Santorum spent a total of S11 million getting re-elected six years ago.) Hillary Clinton has stumped here, as has President Bush. As many as four Republican congressmen in eastern Pennsylvania swing districts could be ousted by a Casey landslide, or rescued by Santorum's coattails. In the inimitable phrase of Hardball host Chris Matthews (a Keystone native), "Pennsylvania is the hottest race in the country of the United States."

He could have continued: "Unless you're a libertarian."

The not-so-secret twist of Pennsylvania's

Senate race is that both candidates are trying to reshape their parties' coalitions by tacking hard to the big-government, social conservative center. Casey, an old-school liberal on taxes, wages, trade, and union issues, is also an anti-abortion, anti-stem cell research, pro-Iraq war conservative. Santorum, who started his career in 1991 as a tax-cutting, small-government conservative congressman, has evolved into a visionary Republican leader in using government to fund religious charities and pay families to stick together.

These aren't idiosyncratic stances. They're the very key to both politicians' appeal. Casey was personally recruited to run by New York's Sen. Charles Schumer and Pennsylvania's Gov. Ed Rendell, two politicians as devoted to abortion rights as a geek is devoted to Star Wars.

As National Review's John J. Miller reported in an early pro-Santorum piece, Democrats pushed Casey into the race "because they think his pro-life views may deny Santorum a vital advantage. The idea is to get pro-lifers to cast their votes on the basis of anything but abortion."

The Casey run was plotted not long after the 2004 election, when polls convinced Washingtonians that "moral values issues"--abortion, gay marriage--were keeping the Democrats at the kiddie table even as the governing GOP stumbled from blunder to blunder.

"This is a national thing," says Philadelphia Inquirer columnist John Baer. "I don't think this has much to do with the Democratic Party in the state. It's a national tactic to see how it plays. If Casey plays in Pennsylvania, you'll see a push to move the Democrats to the center in other states. This race is sort of a laboratory."

As the incumbent, Santorum didn't have to worry about his party tweaking his positions and turning him into a guinea pig. He sold out his libertarian positions without any prodding at all, thank you.

When he first saw the polls showing him trailing Casey in early 2005, Santorum dubbed himself the Republican champion of a new minimum-wage hike. He proposed a $1.10 increase in March 2005, then voted for multiple Democrat-led compromises that would have raised the minimum wage by as much as $2.10.

Santorum's chest-beating over the increase ignited the conservatives at the Pittsburgh Tribune-Review, who called the senator's newfound love for the poor working man too "liberal"--a label that Santorum spun into a campaign ad. (The photogenic huckster sat at a breakfast table, laughing at the way one paper called him a conservative and one called him too liberal, implying that he, like Goldilocks' favorite bowl of porridge, was just right.)

Before the Casey challenge took off, Santorum took a frontline position bucking up President Bush's campaign to introduce private accounts into Social Security. When he got scared, he sponsored the Social Security Guarantee Act--a mash note of bureaucratic guff that issued "benefit guarantee certificates" to reassure seniors they would get their payouts--which nonetheless allowed Santorum to claim he was protecting the creaking benefits system against any and all changes.

Why did a class of 1994 senator who once promised to cut spending and balance the budget scrap so many of his libertarian policies? Easy: He wanted to win. And entitlement reform and budget-cutting aren't as likely to nab voters as, to pluck one example from his resume, millions of dollars of pork.

"Santorum has supported a ton of appropriations for Pennsylvania," says G. Terry Madonna, the director of Franklin and Marshall College's politics department and the university's influential Keystone Poll. "He's no longer a supply-sider. He no longer supports a balanced budget."

Casey and Santorum, in their long march away from libertarian positions, have started the teeth of their party's faithful gnashing. Pro-choice Democrats howled at the Casey nomination; former NARAL Pro-Choice America head Kate Michelman loudly mulled an independent run which, come election day, would have provided Santorum with a Nader-shaped wedge back into his Senate office. Fiscally conservative Republicans were almost as angry at Santorum's record, especially his embrace of the state's Single Bullet Theory-proving liberal Republican Sen. Arlen Specter in his 2004 primary against Rep. Pay Toomey (who took the helm of the Club for Growth, an advocacy group that pushes for a seriously fiscally conservative GOP, after his narrow 51-49 loss).

But as angry as social libertarians and economic libertarians were at the candidates, in the end, they caved. Michelman passed on her run, and no contender emerged to punish Santorum's apostasy.

"Democrats really want to beat Santorum," Madonna explains. "The activists and Club for Growth people who were angry at Santorum have come around. There's kind of a classic squeeze play going on, and both sides are pretty practical about the choices they have."

The immediate effect of this squeeze play has been to transform the Santorum-Casey race from an ideological clash of the titans to a battle of dull and duller. The long-term effect could be, as John Baer speculates, the blueprints from both campaigns getting trotted out by Republicans and Democrats across the country. It's already happening in other states. In August, California's Gov. Arnold Schwarzenegger, an avowed disciple of Milton Friedman, approved a $1.25 hike in his state's minimum wage. His philosophy was expendable; the chance to head off a popular Democratic idea and save his job was not.

In many of the swing districts they need to take over the House of Representatives, Democrats are being counseled to dial back their support of abortion and gay rights while soft-pedaling their criticism of the Bush administration's domestic war on terror. As Republicans inch away from their libertarian stances, Democrats are inching just as hastily away from theirs.

The victor in Pennsylvania will play a major role in the direction his party takes. If Casey wins, the lesson for Democrats will be to cede the moral ground to Republicans, and abandon any litmus test of support for social liberties. If Santorum holds on, Republicans will have learned that the most dogmatic social conservative can survive if he's willing to spend big and abandon classically liberal economic policies.

"If you're a libertarian and you're in this thing," Madonna says, "you don't have a lot of choice. If you're looking for a ray of hope, I don't know where you find it".

David Weigel ([e-mail]) is an assistant editor of reason.