LOS ANGELES (AP) — Three reform-minded candidates running for the Los Angeles Unified school board raised nearly four times the donations of their union-backed opponents, but won only one of the slots outright with another headed to a runoff.

In Tuesday’s election, reformer incumbent Monica Garcia retained her seat, but union-supported incumbent Steve Zimmer also retained his. In a third race with no incumbent running, the candidates are headed to a runoff election in May since neither garnered more than 50 percent of the vote.

Garcia was supported by the Coalition for School Reform, which raised $3.8 million including $1 million from New York City Mayor Michael Bloomberg and $250,000 from Students First, a reform group headed by former District of Columbia chancellor Michelle Rhee.

Teachers union groups donated $1 million to their candidates.