Senator John McCain now faces a new challenge in his bid for re-election in 2016, and she's a fellow Republican.
State Senator Kelli Ward launched her campaign to unseat McCain, who is seeking his 6th term in office.
Ward released a video Tuesday announcing her run.
"Hi I am Dr. Kelli Ward, and I am running for U.S. Senator from Arizona. John McCain is a hero, but as a U.S. Senator from Arizona he has too often disappointed conservatives."
Ward is staking out a position to the right of McCain.
"In Washington I will fight for low taxes, strong military policies that empower families and reward personal responsibility," said Ward in the video.
There are Arizona Republicans who don't like John McCain, who will vote against him in a primary. Ward is going to have to get those votes to win. Many of those voters made their views known last weekend at Donald Trump's rally in Phoenix.
"I mean right here you have John McCain... (boos) some people don't get it, and I don't think they will be in office much longer," said Donald Trump this past weekend.
The big question is whether Kelli Ward can capture enough of the voters to win.
"You know one of the things about Dr. Ward is she is articulate, and she really does fight for what she believes in," said Jake Hoffman with the Republican Party of Maricopa County.
Ward will face McCain, who has served for five terms, and has a campaign war chest of over 4 million dollars.