Rep. Flake to seek Sen. Kyl's seat

GOP Rep. Jeff FlakeJeff FlakeOvernight Defense: Terrorism suspected in EgyptAir crash; McCain details funding plans Overnight Finance: Path clears for Puerto Rico bill | GOP senator casts doubt on IRS impeachment | Senate approves .1B for Zika Overnight Tech: Trade groups press NC on bathroom law MORE (Ariz.) will announce Monday that he is running for the Senate in 2012.

According to a Republican source familiar with his plans, Flake will hold an 8 a.m. Mountain Time news conference in Phoenix to declare his candidacy to replace Sen. Jon Kyl (R-Ariz.), who is retiring. The seventh-term congressman has long been rumored to want a spot in the upper chamber.

Flake appears to be the candidate of choice among national Republicans for the open-seat race. Right after Kyl announced his retirement last week, GOP insiders pegged Flake as the early front-runner, despite the potential for a contested primary. 

He's also a favorite of the Club for Growth, which has already publicly urged him to jump into the race.   

Flake could face a crowded GOP field. A number of Republicans, including Rep. Trent FranksTrent FranksDems: House GOP just like Trump Supreme Court wrestles with corruption law House GOP reignites push for budget plan MORE (Ariz.) and former Rep. J.D. Hayworth (Ariz.), have said they are also considering running. 

Democrats are also targeting Kyl's seat as a pickup opportunity, and some party members in Arizona are holding out hope for the recovery of Rep. Gabrielle Giffords (D-Ariz.), who, before she was shot at a public event in January, told staff she would run for Senate if Kyl retired.

This post was updated at 7:40 a.m.

More in Presidential races

Sen. Boxer fires back at Sanders aide: 'He wasn't there'

Read more »