Mills has been a popular governor in the state and was the top choice of a national Democrat establishment, but her campaign never gained momentum.

The decision clears the way for progressive Graham Platner to face Sen. Susan Collins in a must-win race for Democrats.

Gov. Janet Mills has suspended her Democratic campaign for U.S. Senate, making way for political novice Graham Platner to face Sen. Susan Collins.

Maine Gov. Janet Mills suspends US Senate campaign, clearing path for progressive candidate Graham Platner. Schumer and Gillibrand support Platner.

Mills has been a popular governor in the state and was the top choice of a national Democrat establishment, but her campaign never gained momentum.