LEWISTON — Charlie Summers and Angus King both sought to stake out the high ground Tuesday as the pro-jobs candidate for Maine’s U.S. Senate seat.

Summers, a Republican, made three campaign stops around the state with the national political director of the U.S. Chamber of Commerce. “He’s someone that understands the free enterprise system,” Rob Engstrom said after a news conference outside Simones Hot Dog Stand.

Additional Photos

Gregory Rec/Staff Photographer: Charlie Summers, Maine's Secretary of State and a Republican candidate for U.S. Senate, photographed during a GOP forum at Harriet Beecher Stowe Elementary School in Brunswick on Wednesday, May 2, 2012. Staff Photographer

King, meanwhile, visited shoe factories in Madison and Skowhegan and called for continued trade protection for New Balance athletic shoe company. “There are more than 900 jobs at stake in Maine, and it would be a terrible blow to the region and the state if these jobs are lost,” said the former governor, who is running as an independent.

Cynthia Dill, the Democratic nominee, joined in by issuing her own statement supporting fair trade protections for Maine workers. “There’s no reason at this time to consider dropping tariffs against foreign products that compete unfairly against those produced in Maine,” she said. Jobs and the economy have been the focus of the campaigns from the beginning. A Portland Press Herald poll in late June showed they are by far the biggest issues on the minds of Maine voters.

But the debate over who is the best candidate to create and protect Maine jobs has heated up in recent weeks after the intervention of the U.S. Chamber.

Maine is one of 13 states where the Chamber is spending money to elect Republicans in hopes of winning a Republican majority in the U.S. Senate. The Chamber endorsed Summers last month and spent $400,000 to air a television ad criticizing King, the independent frontrunner.

The ad called him the “King of mismanagement” for increasing the state’s budget as governor and leaving office with a $1 billion gap between revenue and spending. The King campaign quickly assembled business leaders to talk about his pro-jobs record as governor and said the budget gap followed a downturn in the economy.

Engstrom would not say Tuesday whether the group plans to buy more ads here, but he maintained that Summers has the best business credentials and has a chance to win.

“We think that there’s an opening here in this race,” Engstrom said. “We’re going to continue to be aggressively involved.”

Engstrom praised Summers as someone who grew up in a small family business — a hotel — and understands the need for less regulation. He said Summers also opposes the Affordable Care Act, or Obamacare, and supports the Keystone XL pipeline and domestic oil exploration.

King has not yet taken a position on the controversial XL pipeline project — which would send oil from western Canada to Texas refineries, and would not directly affect Maine — saying only that it should be subject to all environmental rules. Dill opposes it.

Both King and Dill support the health care reform law and oppose drilling in the Alaskan National Wildlife Refuge.

King, who founded an energy conservation business in the late 1980s, issued a written statement Tuesday in response to the Chamber visit. De-regulation isn’t always the best way to protect jobs, he argued.

“I certainly know what government should and shouldn’t do for business,” King said. “But there are cases like New Balance in Skowhegan where if government got out of the way entirely we would lose those jobs — and they would be shipped overseas,”

Ongoing trade talks with Vietnam have raised concerns about a current tariff on athletic shoe imports. King issued a statement Tuesday saying he supports free trade but that the tariff allows for fair trade and protects the New Balance jobs.

“To even contemplate — let alone actively negotiate — a step that would result in jobs being lost anywhere in the country – in this fragile economy is simply unacceptable,” King said.

Summers also said New Balance and its jobs need to be protected, and that free trade agreements need to be revisited in other industries as well.

“I’m very much a supporter of free trade,” Summers said. “But with companies like New Balance, you have to make sure they are able to compete.”

The U.S. Chamber is not affiliated with the Maine State Chamber of Commerce, which does not endorse national candidates and has disassociated itself from the ad campaign.

The national group’s involvement in the Maine Senate race has drawn criticism from some in Maine’s business community.

The Maine Small Business Coalition criticized the group’s ads and issued a news release Tuesday telling the U.S. Chamber to “go home.”

“It’s important for people to know that the U.S. Chamber doesn’t represent local businesses. What they represent is a far-right ideological agenda,” said coalition member Suzanne Kelly of Kelly Realty Management in Bangor.

Small business owners are frustrated that the wealthy national group makes it more difficult for them to have their voices heard, said Coalition Director Kevin Simowitz. The coalition, for example, has supported the Affordable Care Act as a way to help small employers, he said.

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