The Shoalwater Bay Casino in Tokeland, Washington, on Dec. 6, 2022. (Karina Brown / Underscore News) Editor’s note: This story was produced through a collaboration between The Oregonian/OregonLive and Underscore News. The Data-Driven Reporting Project supported Underscore’s work on this story. A lawsuit in Washington state and another case before the U.S. Supreme Court are part of a coordinated campaign that experts say is pushing once-fringe legal theories to the nation’s highest court and represents the most serious challenge to tribal sovereignty in over 50 years. Maverick Gaming, which operates 19 card rooms in Washington and casinos in Nevada and Colorado, is challenging a 2020 law that allows sports betting…