It’s “poetic justice” that Joe Biden’s win was cemented in Philadelphia, where the founding fathers signed the Constitution that President Trump has shown “disrespect” for, the city’s former mayor and ex-Pennsylvania governor Ed Rendell told The Post.

The city’s nearly 600,000 votes — 80 percent of them cast for Biden and Kamala Harris — help tip the ticket to victory.

“This is the cradle of democracy,” Rendell says of Philly, where in 1787, the Constitution was signed at Independence Hall, a short walk from the Convention Center where the last of the city’s 75,000 absentee ballots were still being counted Saturday.

“And I think Trump did a lot of things to strain our democracy, and disrespect our Constitution,” Rendell said of the president.

“So perhaps there is some poetic justice that we play a pivotal role” in Trump’s defeat, said Rendell, who was mayor from 1992-1999, governor from 2003 to 2011, and chair of the Democratic National Committee from 1999 to 2001.

The last few thousand of Philadelphia’s absentee ballot votes will be tallied at the Convention Center throughout the weekend.

They can’t change the election — they number far fewer than Biden’s 40,000-vote margin in the state, and have been running 75 percent in Biden’s favor throughout Pennsylvania anyway.

Still, Trump-supporting protesters continue to gather at the center, their chants of “Stop the cheat! Joe got beat” drowned out by the celebratory whoops and music of Biden-supporters.

“They’re entitled to their beliefs and their votes,” Rendell shrugs.

“But this was a fair election, and they came close and almost pushed him over the top,” he said.

“But they should respect the process,” he added.  “The process is the greatest in the world. And the proces is what makes America the greatest country in the world.”