The state House has endorsed a bill that would allow NorthWestern Energy to purchase an additional portion of a coal-fired power plant and of a high-voltage power line in southeastern Montana.

The House voted 62-38 in favor of the bill on Monday. It needs to pass a final vote before a Tuesday deadline to return it to the Senate with amendments.

Those amendments stripped language that said NorthWestern could spend up to $75 million on upgrades to the new portion of the Colstrip power plant and include the costs in its rates without Public Service Commission approval.

Supporters of the Colstrip bill forced a delay on a Medicaid expansion bill, which was heard in the Senate on Monday afternoon.