This story was originally published Sept. 28, 2018.

Democratic Congresswoman Kyrsten Sinema of Phoenix announced Thursday her plans for a 2018 run for the U.S. Senate seat held by first-term Mesa Republican Jeff Flake.

"It's time for us to stand up and answer the call. We can change a broken Washington, and make it work again," Kyrsten Sinema says in a campaign announcement video.

Sinema, a three-term congresswoman who's nurtured a reputation as an independent, was the subject of "will she or won't she" speculation regarding a run for the Senate in 2016, when Sen. John McCain was up for re-election, and again this year.

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Will Allison, communications director for the Jeff Flake for Senate Campaign, released the following statement in response to Sinema's announcement Wednesday:

"From her time working on Ralph Nader's campaign to the state legislature to Congress, Kyrsten Sinema has always been out-of-touch with Arizona, and she'll do anythign to hide her progressive record."

Sinema has locked down her swing district and proved to be a prolific fund-raiser, with $3.2 million in cash on hand as of June 30, a solid base for a Senate run in Arizona.

Sinema would face civil rights attorney and political newcomer Deedra Abboud in the Democratic primary.

Flake is viewed as one of the two most vulnerable Republican senators in 2018.

Flake has had high disapproval ratings among Arizona voters, driven down in part by his recent votes for the Obamacare repeal.

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