WASHINGTON (AP) — Louisiana voters will participate in a revamped and stripped-down state primary Saturday and decide the political fate of an embattled Republican U.S. senator targeted for defeat by President Donald Trump.

Sen. Bill Cassidy is running for a third term but first must overcome a Republican primary field that includes state Treasurer John Fleming and U.S. Rep. Julia Letlow, who was endorsed by Trump in January.

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The primary is the president's latest opportunity to exact retribution from his perceived political enemies, including fellow Republicans he considers disloyal. Cassidy has been near the top of that list since his vote more than five years ago to convict Trump in his second impeachment trial following the insurrection by his supporters at the U.S. Capitol on Jan. 6, 2021. Trump was acquitted.

Louisiana is not among the states Democrats are targeting in their effort to retake the U.S. Senate. A Cassidy defeat in the primary would likely result in a Senate GOP caucus even more unified behind Trump and further demonstrate the strength of the president's grip on the party.