Chris Matthews signs copies of his book. (MSNBC)

It was a book party for Chris Matthews, in honor of his new “Jack Kennedy: Elusive Hero.” But when the author picked up the mike at the Hay-Adams on Wednesday, it suddenly felt like a campaign rally. The MSNBC yakker name-checked more than a dozen pals, famous and non, Joe Biden-style.

Sen. Lautenberg and Sen. Kerry are here! . . . Ed Markey! . . . Joe and Mika — best team in the morning, you were great today!. . . and who? And Tina’s here! Tina Urbanski!”

Close your eyes and you could be on the trail for that Pennsylvania Senate race that Matthews mulled but never pursued. Might he turn candidate after all? We tried to ask, but you know authors — they want to talk about The Book. “I don’t know how I did it,” he said. “There’s no extra time when you’re doing six shows a week. When they’d shut down the air conditioning in the office, I’d go work at Z Burger.” He went on, about talking to Bunny Mellon about Jackie Kennedy, about the toughness of Bobby Kennedy: “That’s the fun stuff. Politics isn’t about speeches and debates. It’s about struggling over this stuff in the back rooms.”

There’s our in! So, politics: Thinking about it? Matthews winced. “This is the benefit of not running: I got to write this,” he said. “And this will last.”