Editor's note: This story has been updated throughout.

Matthew Dowd, a political commentator and former strategist for George W. Bush, announced Wednesday that he will not challenge U.S. Sen. Ted Cruz, R-Texas, in 2018.

Dowd had been considering an independent run against Cruz, who is up for a second term. Dowd said this year that he had been encouraged by prominent members of both parties to take on Cruz.

“I’ve decided the best use of my voice is not putting myself in that position and running for that office in that way," Dowd said in an interview with Texas Tribune CEO Evan Smith. "I think the best use of my most authentic voice and where my life is and what I want to do is in a different manner rather than running for office."

Dowd was still critical of Cruz, saying he has been focused on higher office since being elected Texas' junior senator in 2012. "Republicans in Iowa feel more represented by Ted Cruz than people in Texas," Dowd said.

U.S. Rep. Beto O'Rourke, D-El Paso, remains Cruz's most serious competition in 2018, which nonetheless will be an uphill battle for Texas Democrats who have not won a U.S. Senate election since 1988. U.S. Rep. Joaquin Castro, D-San Antonio, had considered a run for months but announced last week that he would take a pass.

Last year, U.S. Rep. Michael McCaul, R-Austin, was encouraged to challenge Cruz after the senator initially declined to endorse then-GOP presidential nominee Donald Trump. McCaul has since avoided questions about whether he is still considering a Senate run.

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