As Donald Trump prepares a – triumphant? – return to Arizona, he may be in for a bit of a rude awakening. Meanwhile, Republican politicians should be moving to DEFCON 1.

Nearly 55 percent of likely Arizona voters now give a thumbs down to President Donald Trump, according to a new statewide poll by HighGround Public Affairs.

Trump, who won Arizona just nine months ago with 49.03 percent of the vote, has seen his approval rating sink to 41.8 percent.

GOP still loves him. No one else does

Oh, the base still loves him. It's everybody else he -- and Republicans on next year's ballot -- should be worrying about.

Trump is still rock solid with Republicans, 74 percent of whom approve of the job he’s doing. But among independent and unaffiliated voters -- people who make up a sizable portion of Arizona's electorate -- the president's approval rating stands at 26.7 percent and 33.3 percent respectively.

“If the president and the GOP fail to expand public support beyond the GOP base, the party may face historic electoral failures in 2018 …,” HighGround’s Chuck Coughlin, a longtime Republican Party strategist, said. “While I am sure he will receive a hero’s welcome inside the convention hall tomorrow, there should be little doubt given this research, which shows that he enjoys single digit support amongst Democrats and less than a third of independent and unaffiliated voters.”

Translation, if you're a Republican running for office next year, you might want to start worrying now.

Will 2018 be 'catastrophic' for GOP?

Coughlin said the mid-term elections could be “catastrophic” for Republicans if Trump doesn’t turn it around. And that is saying something, given that Republicans historically have a 12-point advantage in mid-term general elections.

“Governing is about bringing people together to solve problems. If the president doesn’t get this soon, it could have disastrous results for Republicans, even in this conservative cycle,” Coughlin said.

Speaking of bringing everybody together, the HighGround poll indicated that 63 percent of Republicans support a pardon for former Maricopa County Sheriff Joe Arpaio -- something Trump has said he's "seriously considering." But everyone else stoned the idea. (89 percent of Democrats, 66.6 percent of independents and 69.5 percent of unaffiliated voters.)

The live telephone poll of 400 likely Arizona voters on Aug. 18 and 19, has a margin of error of 4.88 percent.

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