The self-described "America's Toughest Sheriff" has thrown his hat into the ring to replace Jeff Flake in the Senate.

In a tweet announcing his run for Senate Tuesday morning, former Maricopa County Sheriff Joe Arpaio says his single goal is to support the agenda and policies of President Donald Trump.

"I am running for the U.S. Senate from the Great State of Arizona, for one unwavering reason: to support the agenda and policies of President Donald Trump in his mission to Make America Great Again," Arpaio wrote.

The 85-year-old Arpaio was pardoned by President Trump last summer after he was convicted of ignoring a court order related to racial profiling.

“Throughout his time as Sheriff, Arpaio continued his life’s work of protecting the public from the scourges of crime and illegal immigration,” the White House said in a statement at the time about Arpaio's pardon.

Shortly after his initial tweet this morning, Arpaio linked to an interview he gave with The Washington Examiner discussing his Senate run.

“I am outspoken. I’m looking forward to it. Let them come. They’ll have their political firing squads and bring tons of money here, because they don’t want to lose,” he said in the interview with the paper. “I just want to do everything I can to support our president."

Arpaio enters a crowded field of candidates vying to replace Flake. He will face 

Kelli Ward, a well-known conservative candidate best known for challenging Sen. John McCain in 2016 and as well as Rep. Martha McSally, who is expected to enter the race on Friday.

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