“WHEN I SAY dirt, you’re going to say farmer. Got it?” The crowd packed into a small room just off Main Street in Bozeman, Montana, quickly obliges the MC. “Dirt!” “Farmer!” “Dirt!” “Farmer!” Thus begins a rally for Jon Tester. “I’ve never had a wide margin of victory, and I ain’t going to have one this time, either,” warns the third-term Democrat, who is running for re-election to the Senate in November.