"Any member [of Congress] who feels themselves at risk is getting attention from the proper authority," Hoyer said.

Tempers flared on Saturday and Sunday - both inside and outside of the Capitol - as lawmakers prepared to vote on the contentious health care reform legislation. Hundreds of protesters gathered to voice their opposition to the health care bill. Many were members of the Tea Party movement, which is made up of loosely organized groups of grass roots conservative, Libertarian and anti-tax activists who oppose the Democrats' health care plan, saying that it imposes too much government involvement in the economy and people's lives.

On Saturday, Democratic Representative Emanuel Cleaver of Missouri was spat on by an angry protester as he approached the Capitol. And openly gay Democratic Representative Barney Frank of Massachusetts was the target of a homophobic slur.

Democratic Majority Whip James Clyburn says the jeering and anger from protesters reminded him of the abuse he was subjected to as an African-American civil rights protester in the 1960s.

"What I saw on Saturday especially, out in the streets, and what I heard was very reminiscent of that history," Clyburn said.

Clyburn urged Republican leaders to join Democrats in publicly condemning anyone who encourages threats, vandalism and violence, saying that "silence is consent."

Republican House Minority Leader John Boehner of Ohio told Fox News that violence and threats are "unacceptable" and called on opponents of the new health care law to speak with their votes, and to get involved in politics.