The odd-couple pairing of party honchos was part of a panel presented at Penn's Law School and sponsored by the Bipartisan Policy Center, a Washington nonprofit. Founded in 2007, its stated goal is political compromise through "reasoned negotiation and respectful dialogue."
The panel also included Theresa Brown, BPC's director of immigration policy; business-management guru Osagie Imasogie; Kristi Boswell, director of congressional relations for the American Farm Bureau; and Pennsylvania AFL-CIO president Richard Bloomingdale.
It began while the Republican Conference of the U.S. House of Representatives, meeting in Maryland, was internally circulating its immigration reform "principles," which were promptly leaked to the press.
The principles reportedly call for "legalization" for many of the nation's estimated 11.7 million undocumented immigrants, but not a path to citizenship.
For some advocates on both sides, that will be a sticking point.
"But the American people understand, the immigration system we have now stinks," said Barbour. "The real issue is legalization, so [immigrants] don't have to worry if they run out of gas on the interstate" that they will be found out and deported.
Although the farm bureau supported the Senate's comprehensive immigration reform bill, which passed in June and included a 13-year path to citizenship, Boswell's group is looking for labor stability in an industry where about 70 percent of the workforce is falsely documented and vulnerable to law enforcement raids.
For now, she said, her group "advocates for an earned adjustment" of immigration status, with details to be worked out.
Describing himself as "Nigerian by birth, American by choice," Imasogie cited Fortune 500 statistics and said the perception of immigrants as a drain on the economy was "fundamentally flawed."
Immigration reform "is good for committed capitalists," he said. "If we do not do this, we are shooting ourselves in the foot."
Because immigrants tend to migrate in their prime working years, and produce more children than the domestic population, said Brown, they help replenish the nation's workforce, slow the aging of America, and contribute to the solvency of the Social Security trust fund.
Rendell advised the 60 or so people in the audience to write and e-mail everyone in Pennsylvania's congressional delegation to make their preferences known.
In an election year, with some GOP lawmakers fearing a challenge from tea party candidates, he said, "there's not a chance that we'll get a bill in 2014 until the primary season is over."
He ended with an anecdote on a Rolling Stones concert he saw on TV.
" 'You can't always get what you want,' " he said, quoting the famous song. "But what's the second line?"
" 'If you try sometime, you just might find you get what you need,' " he said with audience accompaniment.
"That," he said, "should be emblazoned on the forehead of every congressman and congresswoman in Washington."