There are many reasons why Democrats should hope that President Obama is reelected next month. The substantive policy differences on issues ranging from marriage equality to tax policy, the likely people whom each candidate would put on the Supreme Court during his presidency and the frightening prospect of the lasting harm a Romney administration backed by a Tea Party dominated House of Representatives could do to our country, are clear.

Another issue, which has not received as much attention but is significant, is that if President Obama is defeated in his bid for reelection, it could lead to fissures in the Democratic Party that could damage the party's electoral hopes in the next few elections. At the presidential level, the Democratic Party has been remarkably free of meaningful conflict in the last decades. In both 1996 and 2012, incumbent Democratic presidents avoided a primary challenge. This may seem natural today but before Bill Clinton, the previous three Democratic presidents seeking reelection had faced strong primary challenges or major third party challenges from people previously identified with the Democratic Party.

The years from 1996 through the present have been a period of unusually strong unity for the Democratic Party. The deep divisions between north and south and the liberal and conservative wings of the party which defined much of Democratic politics in the second half of the 20th century have been considerably less visible during the last 15-20 years. Even the presidential primaries in the Democratic Party, which were competitive in 2000 and very competitive in 2008, were primarily driven by personal and demographic differences rather than substantive disputes over vision or ideology.

If President Obama loses, this could change as questions that are just below the surface of Democratic politics could become more significant. Foreign policy, which has in previous generations divided the Democratic Party, could again become a major issue as some within the party will want to stay with the active internationalist foreign policy of the both President Obama and President Clinton, while others might call for a more restrained and less expansive foreign policy, citing financial limitations as well as differing visions of the role the U.S. should play in the world could drive this.

Similarly, a Romney victory could spark a debate within the Democratic Party about whether President Obama's approach to the poor economy was the right one. Many will defend the President, but others will argue that a more progressive economic program with, for example, a larger stimulus would have been better. There will also be some dispute about Obama's failure to take a stronger position regarding the excesses of the financial sector.

Even if Obama wins, he will not be able to run again in 2016, so the nomination may be contested, but there will likely be a consensus within the party that Obama's presidency was a successful one. Accordingly, the primary will be defined by a struggle to claim the Obama legacy rather than to challenge it. An Obama victory in 2012 will probably be enough to hold the Democratic Party together for at least another cycle, but a defeat at the polls will accelerate debate and contestation within the party.

The certain frontrunner for 2016, if she decides to run, will be Hillary Clinton. Clinton would be a very formidable primary candidate but also one who is almost synonymous with the Democratic Party establishment. A Clinton candidacy will look very different if it occurs while President Obama is wrapping up his second term. In that environment, few will seriously challenge Clinton, who will likely enjoy unified support from both the Obama White House and the Clinton people who still play a very critical role in the Party.

A Clinton campaign, however, will look very different if it occurs following a Democratic defeat in 2012. If the Obama presidency is viewed as having failed, and gives way to disagreement on major issues within the party for the first time in a generation, an establishment candidate like Clinton would be vulnerable to an opponent with more independent credentials willing to take on the Clinton-Obama line which has defined the Democratic Party for the last 20 years. Clinton would probably still be nominated if she ran, but the internal Party dynamic would be different, and the possibility of a strong challenge from outside the party establishment would be real.

If Obama loses next month, the debate within the Party will essentially be whether President Obama was too timid or too bold. This debate, particularly if Clinton does not run and there is no clear frontrunner in 2016, will continue into the next presidential primary and disrupt the unity which has been such an important part of the Democratic Party resurgence of the last two decades. It may lead to a divisive primary, but it may also lead to an important discussion within the Democratic Party. Either way, should the President not get reelected, it will probably be unavoidable.

Lincoln Mitchell