Koochiching County Commissioner Rob Ecklund won a commanding victory over his three DFL opponents in the race to replace the late Rep. David Dill in northeastern Minnesota.

Ecklund’s victory indicated the continued influence of labor unions that strongly supported his candidacy, as well as broad local support for controversial copper-nickel mining projects that residents hope will bring economic revitalization to the region. The second-place finisher, Bill Hansen, opposed the projects and took heat for doing so during the campaign.

As winner of the traditionally DFL-leaning district, Ecklund will face Republican Roger Skraba and Kelsey Johnson, who is running as an independent, in the special election on Dec. 8.

The district is the largest in the state by area, roughly equal to the state of Rhode Island.

Dill was a conservative DFLer and supporter of the proposed copper-nickel mines like that proposed by PolyMet and Twin Metals and undergoing state and federal environmental regulatory review.

The DFL primary has become a proxy battle over the mines, which supporters say would bring hundreds of high-paying jobs to an ­economically troubled region.

Hansen, of Tofte, owner of Sawbill Canoe Outfitters and the race’s sole opponent of the proposed new mines, was critical of the mines’ environmental effects on sensitive watersheds but also questioned them as an economic development tool, saying the industry will not be sustainable. Hansen won the support of environmentalists and raised more than $32,000, including big sums from the Twin Cities metro.

Ecklund, with roots in the Iron Range labor movement and a supporter of the proposed mines, had stepped up his challenge to Hansen in recent weeks. He received at least $11,000, in $1,000 increments, including $5,000 from labor unions that favor the mining projects. Influential Iron Range lobbyist Gary Cerkvenik also contributed to the campaign.

Heidi Omerza, another candidate, is past president of the Coalition of Greater Minnesota Cities and on the Ely City Council. She had promised to bring state money to the ­district.

Eric Johnson, the final DFL candidate, owns a dental supply manufacturer and a canoe outfitter. He ran as a Republican against Dill last year and lost by more than 2-to-1.