“If you’ve been oppressed so long, it’s hard for you to break out to a new idea,” said Ms. Jones. “And when you’ve been governed by fear and people telling you that the city is going to decline because an African-American person is going to be in charge, then you tend to listen to the rhetoric and don’t open your mind to new possibilities.”

Some of Ms. Jones’s voters said they did not make their choice enthusiastically. The number of votes cast on Tuesday was slightly less than those cast during the City Council election two years earlier, when the city was brimming with international attention in its first campaign after Mr. Brown’s death.

“When you look at it, when the people had an opportunity to change what they said has been an oppressed system, they decided not to get out and change the system,” Ms. Jones said a day after the election. “You cannot complain about a system that you are unwilling to do the work to change.”

Voters in nearby St. Louis, also a center of activism after the Brown shooting, also elected a white mayor, who received support from the departing white incumbent over a slew of well-known black candidates.

“To me, Missouri as a whole is ground zero” in the fight for racial justice, said Stefanie Brown James, a political strategist. “For Ferguson and St. Louis to not elect black candidates, that frustrates and angers me.”

Ms. Brown James and many other political observers said they were disappointed at the inability of the black political establishment to coalesce around a single candidate in last month’s Democratic primary. Several well-known black politicians ran and split the vote, allowing Lyda Krewson, an alderwoman who is white and who got the endorsement of the current mayor, Francis Slay, to defeat her closest competitor, Tishaura Jones, but only by about 800 votes.

“That really, to me, is the onus on the black community to say, ‘We cannot continue to have the status quo if we want to make our communities better,’” Ms. Brown James said.