About 25 percent of U.S. workers had MLK Day off Monday, 20 years after King's birthday became a federal holiday.
Gallup Polls conducted at the height of the 1960s civil rights movement listed King among the most-admired leaders of the American public just twice, in 1964 and 1965.
From 1963 to 1966, Democratic President Lyndon Baines Johnson was the most admired. Former Republican President Dwight D. Eisenhower topped the list in 1967.
Yet by the end of the century in 1999, King was the second most-admired individual among Americans after Mother Teresa, the Gallup Poll said.