"I think it speaks to the fundamental, endemic corruption of the Democratic Party establishment that you had to pay... multiple thousands of dollars to get into that room."

Unusually loud booing and jeering directed disproportionately at Sens. Bernie Sanders and Elizabeth Warren during Tuesday night's Democratic presidential debate—particularly when the senators criticized billionaire businessman Michael Bloomberg—sparked probing questions about the class composition of the audience packed inside the Gaillard Center in Charleston, South Carolina.

Appearing on CNN on Wednesday morning, retired Sen. William Cohen (R-ME) hammered members of his own party still sitting in the Senate who refuse to take on Donald Trump, saying they are failing the country and themselves by standing by in fear.

Speaking with CNN hosts Poppy Harlow and Jim Sciutto, Cohen said kowtowing to the president is nothing new, but has grown worse over the past ten years.

"Some of it has to do with external pressures, that of social media, talk radio, specific channels that have a particular view and then hammer that view home to the constituents who then pressure the members of Congress," he explained. "But you have to ask yourself: Why are you a senator? Why are you there? Are you acting out of sheer fear that if you speak up and take a position that's controversial you'll be punished?"