PHOENIX — The GOP primary race for U.S. Senate in Arizona has taken a big turn in favor of Rep. Martha McSally, according to a poll of likely voters.

The congresswoman from Tucson had a 14-point lead over opponents Dr. Kelli Ward, a former state senator, and Joe Arpaio, former Maricopa County sheriff. McSally dominated the OH Predictive Insights poll with 39 percent.

Ward had 24.5 percent, while Arpaio had 13.8 percent. In an April poll, Ward led with 36 percent, McSally had 27 percent and Arpaio 22 percent.

“McSally is starting to tell her story, she’s flush with cash, and she benefited from her pivot to embrace (President Donald) Trump,” Mike Noble, chief pollster with OH Predictive Insights, said in a statement Wednesday.

But nearly a quarter of respondents — 22.4 percent — were undecided about whom they’d choose to replace retiring Republican Jeff Flake.

The Phoenix-based research company surveyed 600 likely Arizona Republican voters June 11-12. Ten percent of the survey takers described themselves as independent.

In the breakdown of respondents by ideology, McSally claimed 43.2 percent among moderates, 40.3 percent from Trump Republicans and 36 percent from Christian conservatives.

Ward’s strongest support came from tea party voters, with 30 percent. Trump Republicans were next at 28.9 percent.

The jump in McSally’s numbers also were linked to improved name recognition.

In the April poll, Noble said, nearly four in 10 voters in Maricopa County had no impression of McSally. She now has 35.7 percent support in the state’s most populous county.

As expected, she was doing better in her home area of Pima County, at 46.3 percent. In rural areas, she pulled in 43.7 percent.

“Early voting (is) approximately 40 days away,” Noble said. “Expect the attacks to start flying as the candidates ratchet up the pressure.”

The winner will likely face Democrat Rep. Kyrsten Sinema in the November general election.

The poll had a margin of error of plus or minus 4 percent.

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