Christie, with his Jersey Boy charm and willingness to butt heads when necessary, has long been a threat to the left wing.
Perry and Romney slugged it out at CNN's debate—and Lone Star strategists Paul Begala and Mark McKinnon butt heads on the outcome.
Together, the two chambers have done little more than butt heads, name names, and point fingers.
to get into a fight or disagreement
Every time she goes to the post office, she butts heads with the postal workers.
imitative of sheep butting heads in conflict
To vie strongly; contend: NBC's new John Laroquette Show butted heads with ABC's Roseanne