Washington (CNN) Florida Republican Gov. Rick Scott launched his long-anticipated challenge to Democratic Sen. Bill Nelson on Monday, officially kicking off one of 2018's most important -- and likely most expensive -- races.

Scott announced his entry into the race in interviews and a video posted on his social media accounts reviewing his two terms as governor.

"I never planned to fit in, and I won't fit in in Washington, either," Scott says in the video . "It's time to shake that place up. We don't need another politician in Washington. It's full of politicians, and that's why it's broken."

Scott has served in the governor's mansion since 2011 and has long been courted to join the Senate race.

Asked if he considers himself a "Donald Trump Republican," Scott told Politico: "I consider myself Rick Scott. I don't consider myself any type of anything." The governor would not tell the publication whether the President would campaign for him.

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