WASHINGTON — His voice exuding disgust, Jeb Bush could have been describing a blistering rash.

“I’m not a United States senator — thank God,” he told a ballroom full of people here the other day.

“Just for the record here, I live in Miami,” he said, in case anyone had failed to grasp his point. “I’m outside of Washington.”

Disparaging Congress, though it is now fully in Republican hands, is nothing new in today’s Republican Party, which has thrived on a hearty strain of antigovernment, anti-establishment intensity. But digs like these are notable, and not only for what they imply in the context of a presidential race with three Republican senators.

Some of the most unforgiving criticism actually comes from those senators, who are just as eager to dissociate themselves from their line of work as their opponents are to remind voters of it.