But voters haven't warmed to Rhee; according to the Washington Post, her approval rating hovers around 44 percent. And her unpopularity may help Mayor Adrian Fenty lose his bid for reelection.
Fenty, who was elected in 2007, put the city's troubled schools under his purview, and he selected Rhee to run the school system.
Tough but visionary, she has wrestled with the teachers' union to fire bad teachers, hire good principals, close underused schools, and streamline a top-heavy administration. She chides teachers who talk about the burdens of teaching students from dysfunctional homes and champions merit pay.
Rhee has committed her share of political mistakes, but she gets results. And if she leaves, it's unlikely her data-driven reforms, which emphasize accountability, would continue. The lesson from her departure would be: Don't shake things up.
Already, Vincent Gray, Fenty's opponent in Tuesday's Democratic primary, has called for slowing the pace of change in the schools. That seems unwise as district schools still fall below the national average.
One of the more striking features of the controversy over school reform is Rhee's alienation from black voters, who account for more than 60 percent of the local electorate. Fifty-four percent of black voters say they are less likely to support Fenty's reelection because he chose Rhee for the chancellor's post, according to the Post.
You'd think that black voters would be building monuments to Rhee. Nearly 85 percent of students in local public schools are black, so black kids benefit disproportionately from the academic gains.
But there is a price to be paid for tangling with teachers. Though it has barely begun, President Obama's Race to the Top program, which emphasizes weeding out poorly performing educators, has frayed alliances between teachers' unions and Democrats.
Schoolteachers exert outsized influence here because, along with civil servants, they are the backbone of the black middle class. While the civil rights movement has given black college graduates far more professional opportunities, teachers are still linchpins of churches, clubs, and other social networks.
And those networks are roiling over Rhee's firings of more than 200 teachers and several principals for poor performance. She also negotiated a union contract that makes it easier to fire bad teachers in the future.
Those are just the changes necessary to eliminate the lazy, the incompetent, and the ill-equipped - teachers whose presence in the classroom is detrimental to impoverished children who start school behind. It's too bad those kids don't have a vote.
Cynthia Tucker is a columnist for the Atlanta Journal-Constitution. E-mail her at firstname.lastname@example.org.