The 2008 presidential election has broken so many political barriers that historians may overlook one unusual fact: When Barack Obama takes the oath of office in January alongside his running mate, Joe Biden, it will be the first time that the president, the vice president, and both of their spouses have worked in higher education. Taken together, the Obamas and the Bidens have amassed decades of experience at colleges and universities. Obama taught constitutional law at the University of Chicago Law School from 1992 until 2004. His wife, Michelle, has worked in the administration at the same university. For the past 17 years, Biden has taught constitutional law at Widener University School of Law. His wife, Jill, teaches English at Delaware Technical and Community College's Stanton-Wilmington campus. No one knows how the academic experiences of the executive-branch principals will shape the next administration. That has not stopped presidential historians and higher-education officials from speculating about how a professor in chief might govern.