Waukesha, Wis. -- Wisconsin Gov. Scott Walker tweeted early Monday morning that he's running for president of the United States.
"I'm in. I'm running for president because Americans deserve a leader who will fight and win for them," he wrote with the hashtag #Walker16 and a link to his campaign website, ScottWalker.com.
Walker will formally declare his candidacy Monday evening in Waukesha, Wisconsin, becoming the 15th GOP candidate in the already massive field.
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In his announcement video released Monday morning on his website and Facebook page, Walker describes a dysfunctional Washington in need of reform, his famous recall election, and a need for a more "safe and stable world."
"America needs new fresh leadership with big bold ideas outside of Washington to actually get things done," he says in the video.
Walker became the first governor in history to win a recall election in 2014.
"We won three elections in four years in a Blue state," he says. "We did it by leading. Now, we need to do the same thing for America."