Superdelegate Math

It is becoming increasingly clear that the outcome of the Democratic presidential nomination will hinge on the votes of the party's so-called superdelegates, elected officials and party leaders who are automatically entitled to attend the Democratic nominating convention regardless of the results of the primaries and caucuses.

Right now Barack Obama has a fairly comfortable lead over Hillary Clinton among delegates elected in the primaries and caucuses. According to the realclearpolitics.com website, as of March 26th, Obama had the support of 1414 pledged delegates to 1247 for Clinton, giving him a lead of 167 pledged delegates. But because of Democratic rules requiring proportional allocation of delegates, it now appears impossible for either candidate to reach the magic number of 2025 delegates needed to win the nomination by the end of the primary season in early June. That means that the nomination will be decided by the 795 superdelegates.

At the moment Hillary Clinton holds a modest lead among those superdelegates who have declared their support for a candidate. According to the most recent National Journal "Superdelegate Tracker," as of March 14th, Clinton had the support of 246 superdelegates to 200 for Obama. But a plurality of superdelegates, 349, remained uncommitted.

Table 1. Current and Projected Delegate Support for Democratic Candidates

Sources: National Journal's The Hotline and RealClearPolitics.

The data displayed in Table 1 shows that after combining the pledged delegates who have already been chosen with the superdelegates who have endorsed a candidate, Barack Obama currently has a lead of 121 delegates (1614-1492) over Hillary Clinton. This table also displays the projected number of pledged delegates that Clinton and Obama will have after the completion of all of the remaining primaries, based on the expected results of those contests. For this calculation, I assumed that Hillary Clinton would win 60 percent of the delegates from Pennsylvania, West Virginia, Kentucky, and Puerto Rico, Barack Obama would win 60 percent of the delegates from North Carolina, Oregon, Montana, and South Dakota, and that Indiana's delegates would be split evenly between Clinton and Obama. I also allocated a small number of remaining delegates from earlier primaries and caucuses based on the overall results in those states. Since Democrats in Michigan and Florida have now decided not to hold do-over primaries, I did not include these states in my calculations.

Based on these projections, the data in Table 1 indicate that Barack Obama will still have a lead of 153 pledged delegates and 107 total delegates at the end of the primary season. Assuming that there are no switches among the superdelegates who have already endorsed a candidate, in order to make up a deficit of 107 delegates, Hillary Clinton would have to win the support of 66 percent of the 349 uncommitted superdelegates.

How likely is it that Hillary Clinton would be able to win the support of 66 percent of the remaining uncommitted superdelegates? This would require a substantial improvement on the 55 percent support level that she currently enjoys among superdelegates who have made an endorsement. Moreover, the data in Table 2 shows that 53 percent of the remaining uncommitted superdelegates are from states that have supported or are expected to support Barack Obama while only 42 percent are from states that have supported or are expected to support Hillary Clinton.

Table 2. Classification of Superdelegates by Type of State

Source: National Journal's The Hotline.

It turns out that there is a fairly strong relationship between the preferences of superdelegates who have endorsed a candidate and the preferences of the voters in their states: 72 percent of superdelegates from Clinton states are supporting Clinton while 63 percent of superdelegates from Obama states are supporting Obama. Clinton is doing slightly better at winning superdelegates from her states than Obama is doing at winning superdelegates from his states. But this may be largely a result of the head start that she had in lining up support from superdelegates because of her early lead in the national polls and her longstanding ties to Democratic leaders. In recent weeks, Obama has been narrowing Clinton's lead among superdelegates, and most of his gains have occurred among superdelegates from states that he carried in the primaries and caucuses.

Based on the pattern of superdelegates supporting the candidate who won the primary or caucus in their state and assigning the remaining primary states to the candidate they are generally expected to support, we can determine how Clinton and Obama are likely to fare among the remaining uncommitted superdelegates.

Even if she is able to maintain her previous rate of success in winning the support of superdelegates from Clinton and Obama states, Hillary Clinton would only be expected to garner the support of 53 percent of the remaining undeclared superdelegates, far short of the 66 percent she would need to overcome an Obama lead of 107 delegates. These results indicate that unless Hillary Clinton can dramatically reduce her current deficit in pledged delegates in the remaining primaries, her chances of gaining enough support among uncommitted superdelegates to win the nomination are minimal.

Dr, Alan Abramowitz is the Alben W. Barkely Professor of Political Science at Emory University, and the author of Voice of the People: Elections and Voting Behavior in the United States

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