LINCOLN, Neb. — U.S. Senate Republicans call Bold Nebraska a faux grassroots group used by non-Nebraska billionaires to funnel money to advance their political agenda, according to a report released Wednesday.

Bold Nebraska has coordinated much of the opposition to the proposed Keystone XL oil pipeline in Nebraska through homespun protests, yard signs and ad campaigns, but the report by the minority staff of the Senate Committee on Environment and Public Works accuses the group of being “an arm of the Billionaire’s Club.”

“It is nothing more than a shield for wealthy and distant non-Nebraskan interests who seek to advance a political agenda without drawing attention to the fact that they, too, are outsiders with little connection to the state,” the report says.