According to the King Online Encyclopedia, from Stanford University's Martin Luther King Jr. Research and Education Institute, King campaigned for Johnson and welcomed his win.
Next, we wondered what the King Center in Atlanta, founded by King's wife, the late Coretta Scott King, had to say about his partisanship. In 2008, Steve Klein, the center's communications director, told the National Journal that "there is absolutely no confirmation that (King) was a Republican. ... He was never a member of any political party — and never formally endorsed any candidates."
Klein noted Coretta Scott King's recall of a 1960 phone call from Kennedy when her husband was in jail. In her book, My Life With Martin Luther King, Jr., she wrote that she took the call but was later unsure what to say about it. "My husband had a policy of not endorsing presidential candidates," her book says. "And at this point, I did not want to get him or myself identified with either party."
The 2008 AP story about the Florida and South Carolina billboards included a statement from King's son, Martin Luther King III: "It is disingenuous to imply that my father was a Republican. He never endorsed any presidential candidate, and there is certainly no evidence that he ever even voted for a Republican. It is even more outrageous to suggest that he would support the Republican Party of today, which has spent so much time and effort trying to suppress African American votes in Florida and many other states."
Friends and associates of Martin Luther King Jr. also objected. The AP article says that the Rev. Joseph Lowery, who co-founded the Southern Christian Leadership Conference with King, "said there is no reason why anyone would think King was a Republican." Lowery told the AP that King almost certainly voted for Kennedy and that the only time he openly talked about politics was when he criticized Goldwater in 1964.
The story quotes Lowery as saying: "That was not the Martin I know, and I don't think they can substantiate that by any shape, form or fashion. It's purely propaganda and poppycock. ... Even if he was, he would have nothing to do with what the Republican Party stands for today."
Finally, we checked with political experts in the states where King spent most of his adulthood. Charles Bullock, a political science professor at the University of Georgia, said King "didn't die a Republican." But Bullock speculated that King could have been Republican in his youth when Southern Democrats were intensely segregationist. William Stewart, a political scientist at the University of Alabama, said that if King was a Republican, he kept it a secret. King focused on civil rights, Stewart said, and "partisan politics wasn't relevant."
Upshot: Raging Elephants points to a King family member whose declaration lends support for its claim that King was a Republican: his niece Alveda. We didn't divine how she reached that conclusion. Another King relative, his son, disagrees, as do respected academic experts and former King associates and friends. The record shows that as a civil rights leader, King avoided partisan identification.
We rate the statement False.