JUNEAU, Alaska — U.S. Sen. Lisa Murkowski cast herself as a champion for Alaska’s fishing industry Wednesday, while independent Margaret Stock questioned the pace of progress by Alaska’s congressional delegation on several issues during a Senate debate in Kodiak.

The fisheries-focused debate, which was broadcast on public radio, also featured Democrat Ray Metcalfe and independent Breck Craig.

Libertarian candidate Joe Miller was absent, on a swing through southeast Alaska instead, according to his campaign. Miller spokesman Randy DeSoto has said Miller plans to visit Kodiak later.

Murkowski, a Republican, defended her record, including in drawing State Department attention to concerns raised by conservationists and fishermen about the impact of Canadian mining activity on waters that flow across the border into southeast Alaska. She said headway is being made but it’s been difficult because the State Department hasn’t seen the issue as warranting urgent attention.

Stock suggested that more could be done. Some of those concerned about the mining activity have urged the involvement of an international commission. Requests for the commission’s involvement must come from the national governments.

The delegation has raised that issue. The State Department, in a recent response to a delegation letter, said it planned to broach options for addressing the concerns with Canadian officials later this month. Murkowski called that “somewhat assuring.”

Wednesday’s debate was the first of four debates or forums to which Murkowski has committed ahead of the November general election. Both her campaign and Stock’s streamed the debate on their Facebook pages.

Miller’s campaign had taken issue with some of the events that Murkowski agreed to participate in, seeing them as friendly to her. Murkowski spokesman Robert Dillon said this should put to rest the accusation that Murkowski is avoiding debates.

Murkowski lost the 2010 Republican primary to Miller but held onto the seat by waging a successful general election write-in campaign.

In this race, Murkowski is touting her seniority and casting herself as a pragmatist. On Wednesday night, she said she’d continue to be a champion for the fishing industry and oceans.

Stock, an immigration attorney, sees the debates as a chance to raise her visibility. One area of concern for her is health care, which she said is not affordable in Alaska. Congress needs to either fix or replace the current federal health care law, she said.

While Stock has won support from factions of the state Democratic party and from prominent Democrat Mark Begich, a former senator, Stock said she is a true independent, motivated to run because she was frustrated by the partisan gridlock in Congress.

Stock has not said who she would caucus with if elected, saying that’s a decision that can be made after the election.

Miller has said that if he wins, he’d caucus with Republicans. In a recent interview, he also said that he has no plans to change his party affiliation from Libertarian.

Metcalfe, who has feuded with Democratic party leaders over the direction of the party, has focused on anti-corruption platform.

In one of the more unusual exchanges during the debate, Metcalfe questioned how Stock could have accepted the endorsement of Begich, who he sees as part of a corrupted political culture. Stock said she was pleased to have Begich’s support. The question drew a reminder from the debate moderator to stick to fishing industry topics.

Craig, a first-time candidate who’s garnered little attention in the race, has expressed frustration with the direction of government. He has said members of Congress need to be more willing to compromise.