Washington ? There, behind the glass, is one of the most famous characters to emerge from the 2000 presidential election.

A Votomatic machine from Palm Beach County, Fla., which introduced America to “butterfly ballots” and various kinds of “chads” — from pregnant to dimpled to hanging, is part of an exhibit on voting that opened Friday at the National Museum of American History.

The machine is behind glass for safety reasons. Curators aren’t concerned it could break loose and wreak havoc with another election; it’s kept there to make sure no one is injured by the accompanying stylus used by voters to punch out chads, the bits of cardboard next to candidates’ names on the much-disputed butterfly ballot.

The exhibit begins with a vast floor map of the United States with color-coded data, county-by-county, showing the way voting is conducted in each area. The Florida machine, one of the newest in the exhibit, stands in a case at one corner of the map.

While visitors can try out other voting machines on display, they can only look at the Votomatic and read the five-step instructions and a warning in larger red capital letters: “Legal time for voting booth is five minutes.”

One of the first visitors, Rob Stewart of Detroit, eyed the machine with a hint of skepticism. He said he wasn’t sure he could master the Votomatic in the allotted time.

“That’s really awful, only five minutes,” he said.

The machine is among the museum’s 90,000 items related to politics. Forty have been chosen for the exhibit, called “Vote: the Mechanism of Democracy.” Curators Larry Bird and Harry Rubenstein will go to this summer’s Republican and Democratic political conventions to collect more materials for the museum’s collection.

Last month a show called “If Elected: Campaigning for the Presidency” opened at the New York Historical Society. It traces campaigning through history, including a CD that plays songs from every campaign.