ST. PAUL, Minn. (AP) — Minnesota’s Republican Lt. Gov. and Sen. Michelle Fischbach is being sued again over her dual roles.

Fischbach automatically ascended to become lieutenant governor in January after Tina Smith was appointed to the U.S. Senate. But she has fought to maintain her Senate seat as Republicans protect a one-seat majority.

A judge dismissed an earlier lawsuit from one of Fischbach’s constituents, mostly because it was filed before legislative session began in February. The same constituent filed another legal challenge Tuesday in Ramsey County District Court.

Fischbach and Republicans say she can hold both jobs. Democrats argue it’s a clear constitutional violation.

Her removal from the heavily conservative district would trigger a special election to determine the Senate majority. Fischbach vows she’d run in that contest.

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