Even as incumbent U.S. Rep. Mike Michaud resisted campaigning Thursday during a shoe factory tour in Norridgewock with a trade ambassador, challenger Kevin Raye went on the attack as he visited a farm in Clinton.

Raye, the Republican state Senate president, visited the Flood Brothers dairy farm in Clinton and said his campaign would focus on agriculture and small businesses.

He touted his recent endorsement by the National Federation of Independent Businesses and noted that the organization gave Michaud, a five-term incumbent Democrat, a rating of zero. Michaud’s campaign has dismissed the rating, calling the organization partisan and partly funded by Republican strategist Karl Rove.

Raye pounced on Michaud’s assessment, saying the group recently awarded its Guardian of Small Business award to eight members of the Blue Dog Coalition, a 25-member conservative Democratic group to which Michaud belongs. Another nine Blue Dogs scored a rating of 50 percent or more with NFIB, but Michaud was one of just two Blue Dogs scoring a zero — the other was Rep. Mike Thompson, D-California.

“He is outside the mainstream,” Raye said of Michaud. “His record in office is not consistent with the record of a Blue Dog Democrat. He has not been one of the people who has been at the forefront of working across party lines and making Washington work. He has voted with his party 93 percent of the time over the past 10 years.”

Raye also cited Michaud’s 11 percent rating from the American Farm Bureau Federation.

Michaud on Thursday morning introduced U.S. Trade Representative Ron Kirk as part of a tour of the New Balance athletic shoe factory in Norridgewock. Michaud, wearing a navy blue suit, salmon tie and gray New Balance sneakers, later said his visit was not a campaign stop and he wouldn’t specify when he would start actively campaigning for re-election.

“It’s hard to say. It depends on my congressional schedule,” Michaud said.

Michaud was scheduled to take an afternoon flight to Washington, D.C., and he noted while introducing Kirk that he was missing votes. “I’ll take whatever lumps I have to,” he said. “This is too important.”

Although Michaud distanced himself from active politicking, his campaign sent out a news release Thursday afternoon blasting Raye. The release says Michaud’s 11 percent rating from the American Farm Bureau Federation was based on 10 votes and that Michaud voted in favor of Maine’s interests, which hurt his national ranking.

“While Mike Michaud was in Norridgewock fighting for Maine jobs, his opponent was touting numbers from an organization that supports a partnership that would directly hurt Maine businesses,” campaign spokesman Dan Cashman said in the release. “That is a stark difference between the two candidates in terms of staying focused on what makes a difference for Maine families.

“Kevin’s negative campaign is what’s wrong with politics today — it’s based on soundbites and misrepresentations, not what is best for Maine.”

Raye’s farm tour

Earlier in the day, during a visit to Maine’s largest dairy farm, Raye listened to the concerns of Flood Brothers employees and called attention to his support for Maine agriculture and small businesses.

Jenni Tilton-Flood, who led a tour of the farm’s milking parlor and hay fields, said the high cost of fuel is the primary concern at Flood Brothers. Its fleet of tractors holds thousands of gallons of diesel, she said, and the increasing costs affect local farming and all areas of the economy.

After the tour, Raye said the country needs a centrist approach to its energy policy.

“We’ve had such polarization in Washington, with one side seemingly wanting to focus solely on conservation and alternative energy, the other side wanting to drill. In fact, we really need all of that,” Raye said. “Those things shouldn’t stand in opposition to each other. We should bring it together. But that’s typical of what happens in Washington. It all becomes a standoff.”

Raye said he intends to model himself after U.S. Sens. Susan Collins and Olympia Snowe — two Republicans who developed a reputation as independent voters.

“Their records show that Maine tradition of looking beyond the party line and reaching across to make things happen — to represent the state, not just a party,” he said.

Later Thursday, Raye also visited a farm in Turner.

New Balance stop

The tour of the shoe factory comes as a free-trade pact, called the Transpacific Partnership, is under negotiation. It’s intended to create jobs in the U.S. by increasing exports of industrial goods, agricultural products and textiles to parts of Asia and the Pacific Rim, but it could lift some tariffs, or import duties, on goods including athletic footwear.

Critics fear it could make imported, foreign-made shoes cheaper to buy than those made in the United States, and hurt American workers.

Michaud was a quiet observer throughout most of the 45-minute tour of the factory floors. He and Kirk — surrounded by almost 20 reporters and photographers — maneuvered around tightly grouped work stations and met with dozens of the factory’s 385 employees. At one point during the tour, Michaud grabbed a finished sneaker and called Kirk’s attention to its label.

“Made in the USA,” Kirk read with a smile.

Matthew LeBretton, New Balance’s vice president of public affairs, said Michaud’s support of the three Maine operations has been enthusiastic, citing Michaud’s delivery of customized New Balance shoes to President Barack Obama in March; his effort to bring Kirk to the Norridgewock; and his efforts to shore up the Berry Amendment.

“When he decides he’s going to do something, he jumps in with both feet,” LeBretton said. “He has a laserlike focus on us.”

The Berry Amendment requires American service members to wear U.S.-made clothing, but allows an exemption for athletic footwear. Michaud wants to close the loophole.

If he’s successful, New Balance would be one of several companies vying for new manufacturing contracts. If New Balance won the bid, the company could add more than 100 jobs in Maine, LeBretton said. The Norridgewock factory is at capacity at the moment, but it could add a second shift to accommodate new workers, he said.