One media report even drew a parallel between McMillian's killing and that of Emmett Till, the 14-year-old boy who was abducted, beaten and shot in 1955 after allegedly flirting with a white woman. His body was found in a river just a few miles south of Clarksdale and galvanized a then-fledgling civil rights movement.
But to call McMillian a trailblazer as an openly gay candidate might be far-fetched. Many in the community did not know his sexual orientation; he hadn't made it an issue in the mayoral campaign, nor had any of his opponents.
The sheriff's department charged Reed with McMillian's murder. Spokesman Will Rooker said there was no evidence to support allegations that it was a hate crime. Reed has not entered a plea.
Still others in Clarksdale questioned why McMillian's death was even newsworthy. It was just another homicide in a town rife with violence. There were about 40 gun-related crimes just in April and May, the local newspaper reported. Drive-by shootings -- even the killing of a 68-year-old grandmother -- don't shock residents anymore.
'They are coming after me'
Unger was in labor for nine hours before Marco was born at 2:11 p.m. April 23, 1979. He was an energetic baby with strong lungs.
When her son was 6, Unger and her husband divorced, and she raised Marco by herself. He was a good kid who threw tantrums when he didn't get his way. "In other words," she said, "he was spoiled."
People told her she was overprotective. She didn't care and catered to her son's every need. She served him breakfast in bed even after he was grown up.
He was furiously curious about the world and loved to learn new things. He liked to skate and bowl with his friends and sang in the church choir. He also spent a chunk of his time around older people and emerged as a leader among his schoolmates. They remember a kid who helped mediate quarrels and stop fights.
"He was the peacemaker," said LaSonya Wilson, 34, who knew McMillian from childhood.
He led the effort to integrate his high school's prom in 1997 and to find the money for the first senior trip (to New York and Washington) since the school was desegregated in the 1970s.
Later, people noticed when he began to talk about bringing change to a town where a lot of black kids just wanted to escape.
"Marco dreamed about putting Clarksdale on the map," Wilson said.
McMillian followed his dreams and made a career for himself, graduating from Jackson State University and then earning a master's degree in development and philanthropy from Saint Mary's University in Minnesota. His résumé was impressive.
He'd served as the international executive director of the historically black Phi Beta Sigma fraternity and as an administrator at Jackson State and Alabama A&M. He moved to Memphis to work as a recruiter for New Leaders, an organization that trains school principals.
In 2009, he received the Thurgood Marshall Prestige Award, and in 2004, Ebony magazine recognized him as one of the nation's top leaders under 30. He proudly showed off a photo of himself with a young Barack Obama.
But McMillian was not without blemish.
He was part of a payroll scandal that ousted Alabama A&M President Robert Jennings, who was found to have hired McMillian in an executive assistant job though he was not qualified and not even present for a few weeks while he was finishing his master's.
McMillian also started his own consulting firm for nonprofit organzations, though its website provided little information. When a reporter from the Clarksdale Press Register covering the mayoral race inquired about McMillian's business, McMillian cut him off, saying he was not required to answer those questions.
Some people who knew McMillian described him as the kind of person who got what he wanted and could come off as pushy and arrogant.
"He never took 'no' for an answer," said Brad Fair, another Clarksdale mayoral candidate who'd known McMillian since their school days.
Fair remembers the day McMillian told him he intended to run for mayor after the incumbent, Henry Espy, decided four terms was enough. Fair was upset. McMillian had promised to support him. Now he was saying he would be his primary opponent.
"He was definitely CEO-minded," Fair said. "He knew how to maneuver to get things he wanted. He knew how to work his way up to the top. He was so confident he was going to win (the mayoral race) -- to the point where I began to think, 'Why am I even running?' "
In the end, Fair ran as an independent so as to not compete for votes against McMillian in the Democratic primary but lost in the general election.
McMillian thought Fair needed more experience. Besides, he told Fair, he was on a mission from God.