EL SEGUNDO, Calif. — Republicans filed a federal lawsuit in an effort to block California's new U.S. House maps a day after the passage of Proposition 50.

The Dhillon Law Group made the announcement Wednesday at a news conference at the California Republican Party headquarters in Sacramento.

The lawsuit was filed by lead plaintiff Assemblymember David Tangipa, 18 California voters and the California Republican Party challenging Proposition 50, alleging it unconstitutionally gerrymanders districts in violation of the 14th and 15th Amendments.

California Gov. Gavin Newsom responded on social media after the lawsuit was announced.

"We haven’t reviewed the lawsuit, but if it’s from the California Republican Party and Harmeet Dhillon’s law firm, it’s going to fail," Newsom wrote on X . "G

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