The court intervened late Tuesday less than a week after a federal judge's decision opened the door to unlimited money in state elections - during the height of election season. 

Conservative groups emboldened by the 2010 U.S. Supreme Court's Citizens United decision have made Montana the center of the fight over many campaign finance restrictions. 

The groups have convinced a federal judge to strike down several laws as unconstitutional, including the cap on contributions given to candidates by individuals and political parties. 

The federal appeals court says the federal judge needs to file his full reasoning for that decision. A brief order temporarily stayed the decision until the court can review the full case.

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