Two dozen advocacy and grass-roots organizations, seeking to make police conduct an issue in the 2013 mayoral campaign, said Tuesday that they were forming a coalition to raise awareness of what they consider racially discriminatory practices by the New York Police Department.

Leaders of the groups involved, which include the Legal Aid Society, the Center for Constitutional Rights and the NAACP Legal Defense Fund, said they planned to pressure political candidates to take positions on controversial practices, like stop-and-frisk, that disproportionately affect low-income minorities.

“We will make it impossible to run for citywide office in New York City without taking a position on stop-and-frisk,” Udi Ofer, the advocacy director at the New York Civil Liberties Union, said, adding that the coalition, called Communities United for Police Reform, would also inform voters about “which candidates stand which way on this issue.”

Robert Gangi, the director of the Police Reform Organizing Project at the Urban Justice Center, a member of the coalition, said he believed that there was unlikely to be significant change in policing under the current administration, and so advocates were focused on the elections.