By the lights of many political strategists and legal analysts, Kane's handling of the furor over the scrubbed sting operation has been uneven at best, incoherent at worst, and, at times, mystifying.
"The bloom is off the rose," said veteran Democratic strategist Ken Smukler.
When Kane was elected in 2012, drawing more votes in the state than President Obama, speculation about her boundless political future started immediately. She fended off serious entreaties from some party leaders who wanted her to run for governor this year.
That was before her handling of the ill-starred sting came to light.
"This kind of story begets others," Smukler said. "If you can't kill it now, you could have to deal with it right into your reelect[ion]."
He and others argue Kane should have preempted the story with her own version, calmly told.
Instead, she blamed sexism and the "Good Ol' Boys club" of Harrisburg for trying to trip her up. Because the sting snared African American officials, she said it was tainted by racial targeting, though the former state agent to whom she attributes that claim has contradicted it.
She has blamed the former state prosecutor who ran the sting, Frank Fina, for dropping fraud charges against the confidential informant who recorded the gifts - when it was she who signed off on that deal in court.
But by far the biggest misstep, political analysts say, was the decision to weaponize Sprague. It looked like an attempt to intimidate those asking questions and reporting on her decision, critics said. And the spectacle of a self-muzzled statewide elected official seemed to diminish Kane; editorials across the state slammed the move.
Why wouldn't the independent, self-described "tough woman" who promised to air out the clubby male-dominated Harrisburg political scene speak up for herself?
It's possible her rapid rise raised expectations too high. "People had an admiration for the way she was elected and started out, but I always doubted whether she had the depth to continue that streak," Philadelphia Democratic consultant Larry Ceisler said. "She hit a wall."
After all, just three years ago, Kane was an assistant district attorney in Lackawanna County, prosecuting sex crimes. She took on the state Democratic establishment to win the nomination for attorney general. To some extent, political pros say, she is making rookie mistakes.
Last week, Kane was giving interviews to television reporters, fighting back with her perspective that the investigation had been tainted.
"Now when I hear her going on offense, I think she's doing better," Ceisler said. "She was dazed and confused, but now she's gotten back off the canvas."
Supporters credit her with several popular decisions. She canceled Gov. Corbett's lottery-privatization proposal and refused to defend the state's same-sex marriage ban in federal court. The notion that she pulled the plug on the sting to curry favor with Philadelphia Democratic allies is a stretch, they say, because she would have benefited far more with voters around the state by charging the officials. That's how a guy named Corbett got elected governor. Remember? As attorney general, he went after corrupt legislators.
Kane's troubles give critics - some of whom might want to stop her rise - a chance to take her down, or at least muddy her up. Her allies have suggested Fina has a motive to hurt her because she is conducting a review of the Jerry Sandusky child sex-abuse investigation, which Fina ran when he was with the A.G.'s Office.
Still, for all the furor in media, political, and legal circles, there is no evidence as yet of any lasting damage to Kane from this episode, no public polling that shows her job-approval or personal favorability ratings dropping.
Political analysts note that the sting story has not gotten wide play on television. Kane does not have to face voters again for 2½ years, and her office mostly does things the public likes - such as warning of tax-time scams and putting away drug-distribution rings.
"Headlines don't tell the whole story," said Marcy Stech, spokeswoman for Emily's List, the Washington political action committee that backs Democratic women who favor abortion rights. The group is among those promoting Kane's potential future.
"She has made tough decisions and put the law above politics," Stech said. "We know Kathleen Kane is authentic, and Pennsylvanians voted for her because she was a prosecutor, not a politician."
Of course, it may help Kane's star continue to rise if she becomes better at the politician's arts - especially at explaining herself.