DES MOINES - Talking over hecklers, Paul Ryan, in his first solo appearance as the Republican vice presidential candidate, met with otherwise cheering crowds at the Iowa State Fair and promised that he and Mitt Romney would boost the nation's economy.

A group of protesters shouted, "Stop the war on the middle class!" throughout the entire speech, but Ryan seemed to never lose his train of thought.

He told the crowd that as a congressman from Wisconsin, he is accustomed to protesters, a nod to the state's recent election to recall GOP Gov. Scott Walker.

"We're used to this in Wisconsin," Ryan said, adding that the protester "must not be from Iowa."

The heckling broke down into a scuffle near the stage where Ryan was speaking, and state troopers had to jump in and drag away a protester.

"Whoa, all right," Ryan said, trying to calm the situation.

A trooper said he saw the protester punch a volunteer.

A few seconds later, the speech resumed and people waved Romney signs in front of protesters' faces.

"Sit down, you jerk!” one Ryan supporter yelled at a man who continued to pump his fist and chant.

Ryan arrived at the fair to a pack of waiting reporters, and his following grew as he walked through the fairgrounds shaking hands and talking to Iowans.

Dressed casually in a red checkered shirt, he spend a moment advising a father to buy a tether for his baby's pacifier.

"My kids always spit them out on the ground," Ryan told the man. "Get a little velcro strap."

While some fair-goers clearly didn't recognize Ryan, others waved excitedly when he walked by.

"He's tall!" one woman exclaimed.

More chaos ensued as Ryan made his exit. He was headed to a fundraiser Monday night in Colorado, followed by a campaign event there on Tuesday.

Iowa Gov. Terry Branstad, a Republican, escorted Ryan out of the fair and seemed apologetic for the disruptions, conveying to Ryan that heckling isn't typical from Iowa audiences.

Ryan seemed to take it in stride, again referencing the Wisconsin recall effort that was marked by protests throughout the state for months.

"It's like a sport," he told Branstad. "Doing all those recall rallies, you just kind of get used to it."

On the way out the gate, a few more protesters shouted after Ryan while a supporter yelled, "Paul, we are counting on you!"

Ryan thanked the supporter, seeming just as relaxed as when he arrived.

"We are counting on you!" he added.