WASHINGTON (Reuters)- When radio host Jerry Klein suggested that all Muslims in the United States should be identified with a crescent-shape tattoo or a distinctive arm band, the phone lines jammed instantly.

"For me to suggest to tattoo marks on people's bodies, have them wear armbands, put a crescent moon on their driver's license on their passport or birth certificate is disgusting. It's beyond disgusting.

"Because basically what you just did was show me how the German people allowed what happened to the Jews to happen ... We need to separate them, we need to tattoo their arms, we need to make them wear the yellow Star of David, we need to put them in concentration camps, we basically just need to kill them all because they are dangerous."

Those in agreement are not a fringe minority: A Gallup poll this summer of more than 1,000 Americans showed that 39 percent were in favor of requiring Muslims in the United States, including American citizens, to carry special identification.

Roughly a quarter of those polled said they would not want to live next door to a Muslim and a third thought that Muslims in the United States sympathized with al Qaeda, the extremist group behind the September 11, 2001, attacks on New York and Washington.

"The level of knowledge is very, very low," said Mohamed Esa, a U.S. Muslim of Arab descent who teaches a course on Islam at McDaniel College in Maryland. "There are 1.3 billion Muslims in the world and some people think they are all terrorists."

And optimists saw signs of change in the November 4 election of the first Muslim to the U.S. House of Representatives, which has 435 members.