As the North Dakota Senate race grows increasingly out of reach, the Democrats' chances of retaking the Senate are becoming more remote.

A new poll from Strategic Research Associates and a local NBC affiliate shows Sen. Heidi Heitkamp, D-N.D., trailing challenger Rep. Kevin Cramer by 16 points. Already the most vulnerable Democrat in the nation, Heitkamp has been hurt in recent weeks by the battle to confirm Justice Brett Kavanaugh to the Supreme Court and an incredible unforced error. A Heitkamp campaign ad identified survivors of sexual abuse, rape, or domestic violence, but then several of the women named said they either didn't agree to have their names released publicly or were not survivors.

The poll represents the third consecutive one since mid-September in which Cramer is ahead by double digits.

Losing North Dakota would likely deal a fatal blow to Democrats' chances of retaking the Senate, because without it, they'd have to win either Tennessee or Texas in addition to every other swing state. Currently, Republican senate candidates Sen. Ted Cruz, R-Texas, and Rep. Marsha Blackburn, R-Tenn., have solid leads over their Democratic opponents.

While it of course is still possible that Democrats could win control of the Senate, their chances are slipping away.