The last time Thomas Frank, author of the best-selling “What’s the Matter With Kansas?: How Conservatives Won the Heart of America,” spoke in Lawrence, he packed the Lawrence Arts Center’s 300-seat auditorium.

“We had to turn people away,” said Raven Bookstore owner Pat Kehde, who coordinated Frank’s June 14 appearance.

Frank, 39, will be in town again Tuesday for a 7 p.m. lecture, discussion and book-signing at the Kansas Union Ballroom, a larger venue. Sponsored by Oread Books, the free event is open to the public.

“I’m looking forward to being back in Lawrence,” Frank said. “The last time was great.”

In “What’s the Matter With Kansas?” Frank, an unabashed liberal, argues that conservatives have found a way to use hot-button social issues like abortion, gun control and gay marriage to turn Kansas against itself. A state once known for its left-leaning populism, he said, now sees little wrong with electing politicians who are quick to coddle the rich, tax the middle class and abandon the poor.

And what’s happened in Kansas, he said, is going on all across the country.

“It’s all about class warfare,” Frank said during a telephone interview from his hotel room in Cedar Rapids, Iowa. “Abortion, guns, gay marriage — they’re all proxies for class anger and anti-intellectualism.”

But none, he said, is more striking, more divisive, than the recent attacks on John Kerry’s war record.

“Oh, that just drips with class anger,” Frank said of the attacks on the Massachusetts senator and Democratic nominee for president. “It’s like Vietnam, the original culture war, has come back to haunt us.”

Frank covered this year’s Democratic and Republican national conventions for New York Magazine. While in New York for the GOP gathering, Frank said, a Republican friend invited him to a get-together for Grover Norquist, head of the conservative Americans for Tax Reform.

“It was at the New York Yacht Club, of all places,” he said. “And while we were standing there surrounded by all this Gilded Age opulence and people pining for the days before there was an income tax, this guy with the Republican Party was passing out the Band-Aids that he’d had made up with the image of a Purple Heart on them — a takeoff on Kerry’s not deserving his medals.

“I looked around and everybody was wearing them. They were a big hit,” he said. “The idea was that if a liberal can get a Purple Heart then Purple Hearts are a joke.”

Frank paused. “Man,” he said, “that was one sick moment.”

This summer, “What’s the Matter With Kansas?” spent several weeks on the New York Times best-seller list.

“This is all new for me,” Frank said. “I’ve never had this kind of reaction before. I’m happy, very happy. But I have to say I’ve been so busy touring, I haven’t been able to write much, which is very annoying.”

Also on Tuesday, Frank will speak at a noon forum at the Garvey Fine Arts Center at Washburn University in Topeka. That event also is free and open to the public.