THERE'S A JOKE that those who comprise Lynne Abraham's base are . . . dead.

It's not true, but her supporters are likely to be reading Modern Maturity, while Jim Kenney's younger ones are reading Rolling Stone. Anthony Hardy Williams' base is black, while Kenney and Abraham will fight for whites. Nobody likes it, but voters tend to vote for someone who looks like them.

Lynne Abraham - as district attorney and judge - dates back to an earlier era, and, to some, her age, 74, is an instant disqualifier. They are, in a word, bigots.

While society has moved to eradicate many -isms - racism, sexism, classism - the old (pun intended) standby, ageism, remains like a stain. Should Abraham arm wrestle Kenney to prove her vitality?

It's fair to ask why she didn't run for mayor earlier, when she was younger.

In 1999, she got the bug and felt the tug and discussed going for mayor, an Abraham confidant tells me. Abraham's husband, radio legend Frank Ford, who was 84 at the time, nixed the idea saying, "I don't have eight years."

Two (John Street) terms later, in 2007, Ford was ailing and failing and Abraham's devotion to her husband ruled out a run. He died in 2009 at age 92.

She's now running and I am in search of her base.

I don't believe gender alone will pull a majority of women - who are a majority of Philadelphia voters - into Abraham's orbit. She was Philly's first woman D.A., but her reputation as a "tough cookie" (thank you, Frank Rizzo) and "The deadliest D.A." (thank you, New York Times) doesn't play well with women. That's not her base.

While in her eight citywide victories Abraham attracted some older, more conservative African-Americans, blacks are her least enthusiastic demographic.

People in minority communities who came into contact with the criminal-justice system "felt a sense of disregard, disrespect and lack of support," says Bruce Crawley, a longtime analyst of Democratic politics. "She will have a difficult time" with minority voters.

She was slow to prosecute bad cops and politicians, but targeted pedophile priests and put a ton of black men on death row. (That they had murdered black people seems almost immaterial.)

Her longevity as an elected official gives her high name recognition, but "high unfavorables" cancel it out, Crawley says. So minorities are not her base.

A veteran political observer says Abraham will draw the grandmothers, especially "the Jewish ones, out of the Center City condos." I'm not so sure.

The majority of city Jews - less than 5 percent of the population - lean liberal. Abraham does not. That is not her base.

Her base, says consultant Larry Ceisler, "are No. 1, the people who voted for her in the races for district attorney" and that translates to older voters.

That would be a problem if you were selling soap, but "older voters vote at a higher rate than younger voters," Ceisler observes.

And older voters generally are less "progressive" than younger voters. Are we on to something?

In "The Next Mayor 2015" on, Tom Ferrick sliced and diced voter numbers and found 121,000 dependable-to-vote Democrats are senior citizens. The "sweet spot" for winning the Democratic primary in a multicandidate race is 100,000 votes, Ferrick says, which looks like good news for Abraham.

Not so fast. Many are African-American and/or liberal, two groups she makes cringe.

Hanging her hat on the gray ponytail/Birkenstock set is a recipe for losing. Lately Abraham's been talking to the college-debt crowd.

She's been meeting with millennials and finds them "inquisitive, bright, engaged and willing to listen with an open mind." She has an open mind, too - she'd like to expand bike lanes and she's OK with decriminalizing pot, although she never uttered those words.

Does the "tough cookie" have a soft center?

In one area, for sure. She is an avowed animal lover, and animal advocates early on launched an online ad supporting Abraham.

That was followed by the commentariat, one of which said she was "a hoarder" who kept 20 cats in her D.A.'s office, turning it into an "animal shelter."

In fact, there were only two rescue cats - Amicus Curiae and Miss Demeanor.

One Abraham base is animal lovers.

She will need more than that.

Phone: 215-854-5977

On Twitter: @StuBykofsky