PORTLAND — A federal judge is due to hear arguments in a lawsuit asking a federal judge to intervene to ensure redistricting is completed in time for next year’s congressional elections.

The Maine attorney general’s office is siding with the plaintiffs who contend there’s no reason to delay redistricting until the 2014 elections. Plaintiffs say the delay is unconstitutional.

But the Maine Democratic Party has intervened. Janet Mills, who’s representing the party, says the state’s current system has worked just fine in the past. She says there’s no way to change it.

Arguments are to be heard today in federal court in Portland.

The National Conference of State Legislatures says Maine and Montana are the only states that allow redistricting to wait until after the 2012 congressional elections.