Life on the campaign trail isn't as glamorous — or as easy — as life in Hollywood, Ben Affleck (search) is learning.

Two days on the John Kerry (search) bus tour were enough for the actor-turned-political junkie.

"I am exhausted," Affleck told the crowd in Zanesville, his last stop.

"I've done a couple of movies, you know. I jump out of buildings. I fight bad guys. I thought I was in pretty good shape, so I thought I'd hang around John Kerry and John Edwards on the campaign bus. How hard could it be?"

"They have worn me flat out," he said.

Affleck, for his part, stuck it out even when some of the candidates own children dropped off.

"We adopted Ben Affleck instead and brought him along," Kerry joked.

Affleck said he joined the campaign to get a behind-the-scenes look at politics, even though he confessed at the first stop that he had slept through most of his experience so far.

His appearances fed rumors that he might have an interest in running for office himself. Democratic Sen. Jay Rockefeller (search) of West Virginia, the wealthy great-grandson and namesake of Standard Oil Co. giant John D. Rockefeller, even volunteered to help.

"You're helping the campaign, and I'll come help yours," Rockefeller said. "You'll need the money."