Montana Republicans have voted to join a lawsuit seeking to limit their primary elections to those registered with the GOP.

The Republican State Central Committee approved the motion by an 83-43 vote Saturday in Helena. They will join a lawsuit filed in U.S. District Court in September against the state and its open primaries.

The lawsuit currently includes 10 Republican county central committees. It asks a federal judge to strike down as unconstitutional Montana laws allowing any registered voter to participate in any party primary.

Republicans complained at the meeting that people not in their party have been voting in their primaries and influencing election outcomes for years.

Montana Secretary of State Linda McCulloch says the state has always had open primaries and she supports the current law.