Rick Santorum’s 18-point loss in his 2006 reelection campaign has been a black mark on his presidential campaign from day one.

But when it comes to costing him votes in this year’s Republican presidential primary, the 2006 Pennsylvania Senate race has nothing on the 2004 version.

While questions about Santorum’s electability stemming from his big loss six years ago have dogged his campaign all along, it may actually be Santorum’s decision to endorse Arlen Specter in the 2004 Keystone State Senate race that really costs him the GOP nomination.

At the time, Santorum’s endorsement gave the moderate Specter conservative street cred and helped him turn aside a primary challenge from Pat Toomey.

Today, it threatens to ruin Santorum’s conservative street cred as he seeks to upend Mitt Romney.

“We’ll forgive incompetence, but not Arlen,” said GOP strategist Dina Fraioli, echoing a common refrain from the conservative base.

While Santorum’s conservatism was called into question on several counts at Wednesday night’s debate, it was Romney’s attack on his endorsement of Specter that really seemed to sting the most.

Santorum gave a somewhat tortured response recalling Specter’s role in shepherding President Bush’s Supreme Court nominees to confirmation – a response that was especially odd given that he’s had plenty of practice defending the endorsement at nearly every turn for much of the last decade. (Not to mention the fact that Specter says Santorum’s version of events is wrong.)

The Specter endorsement has absolutely haunted Santorum for the past eight years. Nearly everywhere he goes, it’s the one thing he did as a senator for which the activist conservative base simply cannot or will not forgive him.

The Post’s Paul Kane wrote a piece on the endorsement in 2004, which provides some insight as to why the grudge remains:

Specter’s primary campaign offered the most obvious example of how Santorum has sought to put the work of the Republican Conference ahead of the ideological purity that his conservative supporters and his liberal detractors alike have come to expect.

Santorum, the third highest ranking Republican in the Senate leadership, makes no apologies for his decision to back Specter. Santorum said that once he made the decision to support his home-state colleague, there was only one way for him go about it -- full throttle.

Some conservatives argue that Santorum’s efforts on behalf of Specter went well beyond a general endorsement. They accuse him of actively undermining Toomey’s conservative supporters and, in the process, putting at risk Santorum’s normally strong ties to activists.

“He made it a crusade,” said Paul Weyrich, a doyen of the right and founder of the Free Congress Foundation. “He left no stone unturned. He went out of his way to try to prevent Toomey from winning.”

And conservatives’ hatred for Specter grew exponentially when he switched parties to become a Democrat in 2009 and gave his new party a 60th vote on President Obama’s health care bill.

That health care vote was the crux of the point Romney made in Wednesday’s debate, and it’s a very smart one.

Even without connecting those dots, though, the Specter endorsement is arguably Santorum’s greatest sin as a U.S. senator, and it’s likely to prove even more damaging even than his own loss two years later.

While many in the GOP are most concerned with electability and beating Obama, Santorum’s base of support is almost entirely separate from that demographic, which he was never going to win anyway.

Instead, he relies on those looking for the true, uncompromising conservative in the race, electability be damned.

His endorsement of Specter speaks instead to political expedience and party politics – the same thing the conservative base dislikes about Romney. And even if the average Republican doesn’t remember the Specter endorsement, the heart of that movement and its leaders will never forget it.

Romney’s campaign is now using that endorsement to plant a seed of doubt that Santorum really is the all-around conservative he professes to be.

“If Rick Santorum couldn’t say no to liberal Arlen Specter, can we really trust him to change Washington?” the narrator says in a new Romney web ad, shown above.

And if that seed takes root, the conservative case for Rick Santorum is severely undermined.


Karen Santorum says her husband’s campaign is “God’s will.”

The AP reports that e-mails released by the state of Alaska show Sarah Palin wanted to quit as governor months earlier than she actually did, citing mounting legal bills and the overwhelming scrutiny faced by her family. “I can’t afford this job,” she wrote at one point.

Comedian Bill Maher cuts a $1 million check to Obama’s super PAC.

A new Franklin and Marshall College poll in Santorum’s home state of Pennsylvania shows him leading Romney by nearly 30 points.

A gay marriage bill is on its way to Gov. Martin O’Malley’s (D) desk in Maryland. O’Malley has said he will sign it. And Maine voters will again vote on a gay marriage measure after defeating it 53 percent to 47 percent in 2009.

Former Wisconsin governor Tommy Thompson (R), running for Senate, tells his primary opponents to “get the hell out of my way.”

Seven states file for an exemption from Obama’s contraception coverage mandate.

Rep. John Sullivan (R-Okla.) apologizes for a joke about killing U.S. senators.

Rep. Mark Critz (D-Pa.) is challenging Rep. Jason Altmire’s (D-Pa.) ballot petitions in their primary matchup, and Altmire’s campaign isn’t happy about it.

A watchdog group says a super PAC supporting Romney’s campaign is breaking the law by running an ad almost identical to an ad the Romney campaign ran in 2007.

Herman Cain defends former congressman Pete Hoekstra’s (R-Mich.) controversial Super Bowl ad while campaigning for the Senate candidate. “I loved it,” Cain said. Meanwhile, a new poll shows Hoekstra gaining ground in the GOP primary.


Marco Rubio’s Mormon Roots” -- McKay Coppins, BuzzFeed

What happens if Romney wins Michigan?” -- Dan Balz, Washington Post

Report: Debt will swell under top GOP hopefuls’ tax plans” -- Lori Montgomery, Washington Post

Santorum Turns His Outsider Argument Inside-Out” – Matt Negrin, ABC News

G.O.P. Fund-Raiser Faces Inquiries Into His Races” – Erich Lichtblau, New York Times

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