As The Inquirer reported Friday, the GOP robocalls and online ads draw links between Abu-Jamal and Democratic candidate Kathy Boockvar by citing legal work her husband did more than a decade ago, long after Abu-Jamal's 1982 conviction for the killing of Philadelphia Police Officer Daniel Faulkner.
The legal work was for a witness who recanted testimony against Abu-Jamal in 1996 and for Abu-Jamal's literary agent, arrested in a 1999 protest. The GOP accusations do not cite any actions or words by Boockvar herself.
In interviews Friday, Democrats and independent observers described the links as tenuous, distorted, and perhaps tinged with racial overtones. Some said the attack could backfire.
Rendell, who was Philadelphia district attorney when Abu-Jamal was prosecuted, said Boockvar "has no association, absolutely, with Mumia, in no way or form helped Mumia."
Boockvar seized on the issue Friday, e-mailing supporters a fund-raising appeal that cites Rendell's comments and says Republicans had launched "a slew of false, negative attack ads against me and my family."
"It has all sorts of overtones. It just stinks," Rendell said, adding that he had offered to do robocalls to help Boockvar in the tightly contested race.
The head of the Philadelphia election watchdog group Committee of Seventy, Zack Stalberg, said that even in an increasingly harsh political atmosphere, the attacks are "particularly egregious and outrageous," and that Fitzpatrick should have offered a stronger response.
"It's probably the worst unfortunate example of one side taking a tiny connection to a candidate's past and blowing it way out of proportion," Stalberg said.
Pointing to a Web ad featuring a grainy photo of Abu-Jamal, who is black, with an image of Boockvar, who is white, superimposed over it, Stalberg said, "It definitely seems as if race is being injected in this campaign in a bad way."
Pennsylvania's AFL-CIO called the attacks "sleazy" and said the labor coalition, which generally favors Democrats over Republicans, would watch Fitzpatrick "dance around" on whether he stands by the ads.
Fitzpatrick's campaign did not respond to a request for comment Friday. In a Thursday interview with The Inquirer, the congressman said questions about whether the ads are fair should be referred to the Washington-based National Republican Congressional Committee (NRCC), which launched the accusations.
Asked several times if he would denounce the attacks, Fitzpatrick said the documents backing up the charges were "troubling" to him.
The NRCC supports its charges by pointing out that in 1996, Boockvar's husband, lawyer Jordan Yeager, represented a witness who recanted her testimony against Abu-Jamal and, in the course of that defense, accused police of intimidation.
In 1999, at a time when he and Boockvar had their own law firm, Yeager also defended Abu-Jamal's literary agent when the agent - then 75 - was arrested for a minor offense while protesting Abu-Jamal's conviction.
"Boockvar's husband accusing the Philadelphia police of pressuring witnesses to the murder of Officer Faulkner is NOT disgusting, but making note of that fact IS?" NRCC spokesman Nat Sillin wrote in an e-mail. "With all due respect, Mayor Rendell needs to take a closer look at the facts."
Sillin issued a similar response to Stalberg's criticism.
As the candidates fight in a moderate district in Bucks and part of Montgomery County, the Abu-Jamal attack fits with a months-long Republican effort to paint Boockvar as a lawyer with ties to radicals.
Such provocative charges might damage the target, but the attacker can also be stained, said Carl Golden, who was a press officer to two Republican governors of New Jersey, Thomas H. Kean and Christie Whitman.
"The trick is to drive the other guy's [negatives] more than yours," Golden said. "When you go too heavily negative, and this one goes awfully, awfully close to that, it carries with it an air of desperation."
But emotional attacks can make a real difference.
Daniel McElhatton, a former Philadelphia city councilman, said he felt a nauseous sense of déjà vu when he read about the Abu-Jamal ads because he faced a similar attack in his 1995 Democratic primary campaign.
That year, his opponent tied McElhatton to the radical group MOVE by pointing out that one of McElhatton's law partners had been a court-appointed defender - more than a decade earlier - for a member of the group charged in the killing of a police officer.
McElhatton, who lost the 1995 race, said Fitzpatrick should renounce the attacks.
"I'd have some respect for the man if he did that," he said, calling the accusations "reprehensible conduct and despicable."
McElhatton and Golden agreed that the target of tough attacks has to move past them or else risk giving a negative story additional life.
The only real way to fight back, McElhatton said, is to "win the election."
Contact Jonathan Tamari at firstname.lastname@example.org or follow on Twitter @JonathanTamari. Read his blog, "Capitol Inq," at www.philly.com/CapitolInq.
Inquirer staff writer Sean Carlin contributed to this article.