BOZEMAN, Mont. (AP) —U.S. Sen. Tester is saying that Republican opponent Denny Rehberg is only out for himself and his "rich buddies."


The two squared off Saturday night in Bozeman for a fourth and final debate — and neither was pulling punches.


Polls show that the race remains tight, ensuring it remains one of the highest-profile Senate battles in the nation as both sides vie for control of the chamber. Montana airwaves have been dominated with attack advertising fueled by millions of dollars in outside spending.


At Saturday's debate, Rehberg immediately went to his central campaign theme by mentioning Tester's support of President Barack Obama policies like "Obamacare."


Tester says "hyper-partisanship" in Washington D.C. is causing gridlock that prevents budget solutions, and says Rehberg embodies that partisanship.