Ascending to the presidency in the midst of a severe economic crisis and an ongoing war on terrorism, Barack Obama faces numerous political and policy challenges. We examine an oft-obscured facet of presidential leadership: the president's relations with his party. We argue that Obama has benefited from and abetted the development of a new relationship between the president and the parties that features presidents as strong party leaders who invest heavily in mobilizing voters, raising campaign funds, and articulating party doctrine. As we show, Obama's party leadership may hold both promise and peril for the practice of American democracy. Just as previous Republican presidents such as Ronald Reagan and George W. Bush used their powers in ways that bolstered their parties, Obama's exertions have strengthened the Democratic Party's capacity to communicate with constituents, mobilize voters, and raise funds. However, Obama must take care to avoid the pitfalls of presidential party leadership that ultimately undermined Reagan's and Bush's presidencies. In particular, recent history suggests that Obama must avoid forms of administrative aggrandizement that alienate citizens from government; and that he must forego leadership strategies that threaten the independence and integrity of the party apparatus.