Former Montana Gov. Brian Schweitzer (D) leads Sen. Max BaucusMax BaucusTrump has yet to travel west as president Healthcare profiles in courage and cowardice OPINION | On Trump-Russia probe, don’t underestimate Sen. Chuck Grassley MORE (D-Mont.) in a new Senate primary poll — and he wants to make sure everyone knows it.

Schweitzer posted on his Facebook page the Public Policy Polling survey showing him ahead Baucus by almost 20 points. The post marked the most public sign that Schweitzer is interested in the seat.

There have long been rumblings that Schweitzer, a popular former governor who was term-limited out of office in 2012, wants to run. Baucus has not said whether or not he'll run again in 2014.

The poll shows that Schweitzer would be stronger than Baucus in the general election as well. While Schweitzer leads most of the Republicans who could run for the seat, Baucus trails some of them, and his edge with the others isn't as large as Schweitzer's.

If the two Democrats do run, the primary will be one of the most closely watched in the country. It also has a good chance to be both bloody and expensive, hurting whoever does emerge from the primary's chances of winning the general election in the Republican-leaning state.