Supporters of a proposed new pipeline across northern Minnesota dropped off postcards and petitions containing 1,200 signatures at Gov. Mark Dayton's office on Friday, the latest move in a drawn-out battle that is weeks away from a regulatory denouement.

The Minnesota Public Utilities Commission is set to decide the fate of the controversial Line 3 project by Enbridge Inc. later this month after three years and several legal fights.

Enbridge Inc. is seeking approval from state regulators to drain and seal up its aging crude oil Line 3 and construct a larger pipeline across a new, more southerly route.

Petitions were signed by "a broad coalition" of supporters that include chambers of commerce, representatives of corn and soybean growers and construction trade unions, said a spokesman for Minnesotans for Line 3, which collected signatures during a five-month statewide canvassing effort.

The group is led by United Piping Inc. CEO Bob Schoneberger, a former Enbridge employee whose company specializes in pipe construction for the oil and gas industry.

Schoneberger did not respond to a request for comment.

Mark Salmon, a retired member of Roofer's Local 96 in Sturgeon Lake, Minn., said the project will add jobs and update aging infrastructure. He signed a card to show his support for what he called "a no-brainer."

"You've got old pipes and new technology that's safer," said Salmon, whose property is not affected by the proposed new route. "If you're worried about the environment, why wouldn't you want something that's safer than something that's been there for however many years and could bust?"

The original Line 3 pipeline was laid in the 1960s. Enbridge says it is aging, corroding and operating at just over half capacity because of safety concerns.

The new pipeline — which would begin in northern Alberta and end in Superior, Wis. — would restore the full flow of oil from Canada.

The company said it would be constructed of stronger steel and enhanced with improved technology to monitor leaks.

Enbridge's preferred alternative route for Line 3 would not cross Indian reservations in northern Minnesota, as the existing pipelines do. But the pipes would travel through land for which the tribes have treaty rights to hunt and fish. The area is rich with lakes and rivers that are essential to cultivating wild rice, which is culturally sacred to the Ojibwe.

In the lead-up to public hearings and a pending decision by the PUC, both sides have mobilized forces.

On Monday, 500 faith leaders delivered their own petition to Dayton and regulators, spelling out their opposition on moral grounds as both a threat to the environment and to Minnesota's Ojibwe people.

Environmental and Indian groups also have protested the move.

Meanwhile, Enbridge has made additional pledges to communities affected by the new route as the PUC vote draws near.

A week ago, the company offered to remove portions of the old pipeline at no cost to landowners who requested it, despite previous assertions that it would cost $1 billion to do so.

Enbridge CEO Al Monaco also said the company would encourage contractors to spend at least $100 million with American Indian subcontractors and employees on the project, which is projected to cost more than $2 billion for the U.S. portion.

If the PUC approves Line 3, construction could begin later this year.

Jackie Crosby• 612-673-4292