Political candidates flock to the Minnesota State Fair like eager 4-H’ers, and this year’s crop of statewide candidates obliged on opening day Thursday by showing up to plead for votes — and to take a few swipes at one another.

At 6 a.m., as the first fairgoers streamed through the main entrance, both Democratic Sen. Al Franken and his Republican challenger, Mike McFadden, stood outside the gate, shaking hands. DFL Gov. Mark Dayton had a full first-day schedule of both political and official events that included a dousing of icy water, while Republican opponent Jeff Johnson showed up to challenge the incumbent to more debates.

Dayton called the fair a potent draw for candidates. “You stand in one place and the rest of the state comes passing by,” he said shortly before he took a 45-minute shift shaking hands, chatting with supporters and posing for cellphone pictures at the DFL booth.

Just as it’s easy to find politicians at the fair, it’s not tough to find fairgoers with political opinions.

Joe Alfano, a retired teacher from southwest Minneapolis, stood in a line of about a dozen people waiting to greet the governor.

“I’m pleasantly surprised with how well he’s done,” said Alfano, a Democrat who said he was initially unhappy four years ago when Dayton become his party’s candidate for governor.

“He proved me wrong,” Alfano said. “I feel like the state is in a better place now, and I think his leadership has a lot to do with it.”

A couple blocks from the DFL booth sits the Johnson for Governor booth: red paint, white trim and corrugated metal that summons the image of a barn. Joe and Judy Konicek, retirees from Maple Plain, stopped to grab a handful of buttons. One read: “Re-elect Dayton? Um … no.”

The couple described themselves as Republican-leaning independents. Joe Konicek said he studied up on Johnson’s work as a Hennepin County commissioner, and was impressed.

“He votes no on everything, and that’s what I want in a politician,” Konicek said.

The Koniceks were disappointed that they missed seeing Johnson, who had stopped briefly at the booth about 15 minutes earlier. Johnson had been there for a news conference where he called on Dayton to join him in 13 debates rather than the six the incumbent already agreed to.

Unlike some past election years, there are no gubernatorial or Senate debates planned for this year’s fair.

“You’ll not find a broader cross-section of Minnesotans than you will at the State Fair,” Johnson said. Dayton called Johnson’s demands “a contrived issue” and said six gubernatorial debates would be plenty for voters to draw distinctions. They’re scheduled to happen between Oct. 1 and Nov. 2, with three in the Twin Cities and one each in Duluth, Moorhead and Rochester.

McFadden and Franken also squabbled about debate scheduling at the fair. McFadden asked for six, but Franken agreed to three more on top of an early August debate where they talked farm issues.

Johnson’s news conference took a detour when Matt Faue, a union pipefitter from Corcoran, jumped in to confront the candidate. Faue told Johnson that many union members would like to support Republicans but feel they can’t trust the party following high-profile GOP-union clashes like the one in Wisconsin in 2011.

“If the Republicans can learn to play nice with unions, a lot of the union people could come to the Republican side,” Faue said. “Trust me, I’m not a liberal. But I have to vote to keep my job.”

Johnson was quick to note his own parents were lifelong union members — his father drove a baked-goods delivery truck, while his mother was an employee of Becker County.

“My strong belief is the only way you can make a business work is work with the unions. Because if all you’re doing is butting heads, the business will not succeed. It will fail,” Johnson told Faue. “We’re probably not going to agree about all union-related issues, but I think it’s really important that Republicans, Democrats and everybody else understand that big chunks of the population are hardworking people, whether they’re in unions or not.”

Faue later said he was not convinced by Johnson’s argument and is still likely to vote for Dayton.

Johnson left a few minutes later for campaign stops in southern Minnesota, but said he’d be back to campaign more at the fair at least 10 more times in the next 12 days.

Dayton, meanwhile, traversed the fairgrounds in a golf cart, finally ending up at the 1500 ESPN booth to appear on the “Garage Logic” radio show. The governor had agreed to participate in the ALS Association’s “Ice Bucket Challenge” fundraiser, a national sensation in recent days that has helped the organization raise more than $40 million to fight what’s often called Lou Gehrig’s disease.

Minnesota Twins owner Jim Pohlad had challenged Dayton to donate or take the icy bath. Though he went for the latter, Dayton said he would also make a personal contribution to the association.

Sitting on a wooden step in front of host Joe Soucheray, the governor maintained his trademark stoicism as the show’s producer emptied a Minnesota-shaped pitcher of ice water over his head.

When it was done, Dayton smiled, licked his lips, arched his eyebrows and stood up.

Upon completing his challenge, Dayton challenged Franken to do likewise.

Franken’s campaign said he would do so on Friday. U.S. Sen. Amy Klobuchar, a Democrat, also took a bucket of icy water at the fair.