Montana State Auditor Monica Lindeen (D) told the Missoulian that she "decided I can best serve Montanans in the job I was just reelected to do" and that she didn't want to depart Montana fo Washington, D.C.

Her decision comes on the heels of former Montana Gov. Brian Schweitzer's (D) surprise decision not to run for the seat. The popular former governor's move likely dealt a blow to Democrats' chances of holding onto the seat in the Republican-leaning state.

Other Democrats mulling a run include EMILY's List President Stephanie Schriock (D) and Montana state Superintendent Denise Juneau (D).

On the GOP side, Rep. Steve Daines (R-Mont.) has been seriously weighing a possible bid.