Senate Majority Leader Mitch McConnell Addison (Mitch) Mitchell McConnellOcasio-Cortez to voters: Tell McConnell 'he is playing with fire' with Ginsburg's seat McConnell locks down key GOP votes in Supreme Court fight Video shows NYC subway station renamed after Ruth Bader Ginsburg MORE's (R-Ky.) allied super PAC has launched a new ad blasting Sen. Jeff Flake Jeffrey (Jeff) Lane FlakeJeff Flake: Republicans 'should hold the same position' on SCOTUS vacancy as 2016 Republican former Michigan governor says he's voting for Biden Maybe they just don't like cowboys: The president is successful, some just don't like his style MORE's (R-Ariz.) primary opponent, amid concerns that President Trump could side with the challenger over the incumbent senator.

The move is part of the Senate Leadership Fund's opening salvo meant to protect Flake from the possibility of a Trump-backed primary from state Sen. Kelli Ward, who unsuccessfully ran against Sen. John McCain John Sidney McCainMomentum growing among Republicans for Supreme Court vote before Election Day McConnell urges GOP senators to 'keep your powder dry' on Supreme Court vacancy McSally says current Senate should vote on Trump nominee MORE (R-Ariz.) in 2016. Trump tweeted support last week for Ward, who has already announced her bid, leading to speculation he could officially endorse her at his Phoenix rally on Tuesday.

SLF's new digital ad slams Ward with criticism painting her as a conspiracy theorist, offering a clear sign of what's to come in her bid to unseat Flake.

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The ad criticizes Ward for convening a hearing where Arizonans spoke about their concerns on "chemtrails," emissions left by aircrafts as they fly through the sky. Some believe, without evidence, that the planes are spraying secret chemicals into the air for nefarious purposes, but scientists have repeatedly noted the harmless trails are created by condensation.

Ward's decision to hold that hearing has led to attacks that have long dogged her political bids. She's since said she does not believe in the theory but wanted to provide a forum for her constituents who did and has accused her opponents of using the issue to unfairly tar her as a distraction.

" 'Chemtrail' Kelli has got her head in the clouds with crazy ideas," the ad's narrator says, playing clips of Ward accusing McCain for being "directly responsible for the rise of ISIS."

And it shines a spotlight on her comment after McCain's recent brain cancer diagnosis. In response to the diagnosis, Ward said that McCain should "step away as quickly as possible" and that she should be at the "top of the list" of those who could be appointed to fill a potential vacancy left by McCain.

"Embarrassing behavior, dangerous ideas. No wonder Republicans rejected her just one year ago," the ad's narrator says.

" 'Chemtrail' Kelli Ward. Not conservative, just crazy ideas."

The intense campaign ad comes as Republicans continue to worry about the possibility that Trump could boost Ward's profile with an endorsement.

Trump has been careful to express support for Ward's primary challenge without providing an explicit endorsement, which could allow him to back other potential candidates in a primary. Ward has shaped her campaign around her ardent support for Trump, repeatedly hitting Flake for breaking with the president.