Blake Masters, a close ally to billionaire Peter Thiel and current Thiel Capital executive, launched a bid for the Arizona Senate Monday. As a Republican, he’ll be seeking to take on Sen. Mark Kelly (D-AZ). Masters joins a growing pool of Republican candidates, including Arizona Attorney General Mark Brnovich and solar power executive Jim Lamon.

On his campaign website, Masters champions a total ban on illegal immigration, calling for the government to use “physical walls, surveillance technology, thousands more border patrol agents, and mandatory E-Verify for employers” along the US-Mexico border. Thiel’s Founder’s Fund invested in the border and military surveillance company Anduril, valuing the company at $1 billion.

Masters’ website also vows to “take on the ‘big tech’ platforms — the new public square where free speech is constantly under attack.” However, no clear policy solutions are listed on the site. Arizona is expected to become a key battleground state for both Republicans and Democrats in the 2022 midterms. 

A 34-year-old Tucson resident, Masters rose to prominence by co-authoring Zero to One alongside Thiel in 2014 and serving as an executive in a number of Thiel’s companies. In April, Politico reported that Thiel created the new Saving Arizona PAC in support of Masters’ anticipated Senate run, donating $10 million to fund the PAC. 

Thiel has emerged as one of the biggest donors leading up to the 2022 midterm election cycle. In March, Thiel donated $10 million in support of Hillbilly Elegy author J.D. Vance’s campaign for Ohio Senate. 

Since 2016, Thiel has supported a number of Republican political candidates, including former President Donald Trump. Thiel has been a longtime critic of Democrats and has donated thousands in support of Republican politicians like former Kansas Secretary of State Kris Kobach and Missouri’s Sen. Josh Hawley. Thiel was one of the earliest investors in Facebook.