Though presidential candidates often say that education will be one of their top priorities, the job of education secretary is often among the last cabinet seats filled. While Barack Obama's transition team hasn’t floated any names yet, the education establishment---reformers, teachers’ unions, colleges and universities--has no shortage of candidates. What no one knows is whether Obama is leaning toward someone from the more innovative end of the reform movement (the group Democratic Rep. George Miller, who heads the U.S. House education committee, admiringly calls the “Disrupters”) or a candidate with close ties to the teachers’ unions. Long a key constituency in the Democratic Party, the unions are now under attack by the Disrupters, who see teachers’ protectiveness of tenure and seniority as barriers to dramatic reform, particularly in failing urban schools.

The innovators, who have made key alliances with corporate donors and politicians eager for a faster pace of reform, want one of their own in the top spot. Their favorites include New York City schools chancellor Joel Klein, who has helped transform the country’s biggest urban school system; Jon Schnur, the head of New Leaders for New Schools, who acted as an Obama surrogate during the campaign; Michelle Rhee, chancellor of the Washington, D.C., school system and founder of the New Teacher Project; Kati Haycock, the outspoken head of Education Trust, a nonpartisan powerhouse pushing for bold education reforms, or Wendy Kopp, who founded Teach for America, which funnels new graduates of prestigious colleges into hard-to-fill teaching positions.

The teachers’ unions prefer someone like Linda Darling-Hammond, a professor of education at Stanford who acted as a surrogate for Obama during the campaign or former Gov. Jim Hunt of North Carolina, both reformers who have a long history of working respectfully with the unions on issues like increased teacher professionalism. There’s even talk of Obama choosing one of their own, like Randi Weingarten, the savvy new president of the American Federation of Teachers.

During the campaign, Obama managed to convince both groups that he shared their vision of change. Teachers liked his criticism of the federal No Child Left Behind reform plan as inflexible and underfunded, and his promise that future reforms would be done with them, not to them. The innovators were encouraged by his shout-out to Rhee during the third presidential debate, his call for performance-based pay for teachers and his enthusiasm for the expansion of charter schools. However, when Obama recently put Darling-Hammond in charge of his education policy transition group (immediately raising the perception that she was a candidate for the top job), there were howls of protest from the Disrupters, who fear a return to the more modest and incremental pace of reform that characterized the Clinton years.

What about someone who can bring both sides together? Names that come up in those conversations include former secretary of state Colin Powell, who has long had an interest in education, as well as programs benefiting disadvantaged youth; Arne Duncan, who is well known to Obama as chief executive of Chicago’s public schools as well as a basketball-playing buddy; and Freeman Hrabowski, president of the University of Maryland-Baltimore County, an independent thinker who has been notably successful in attracting and graduating minority students in highly demanding college science and technology programs. Other governors getting buzz include Republican Tom Kean, former governor of New Jersey, former president of Drew University, and chairman of the 9/11 Commission, as well as Democrat Tim Kaine, the current governor of Virginia, who made Obama’s short list for vice president.

If the country’s economic woes slow down, Obama’s ability to boost education funding as promised, he may focus on someone who could wield the power of the bully pulpit as skillfully as Bill Bennett did during the early Reagan years. Powell and Hrabowski would both meet that criteria, while adding racial diversity to the cabinet.