The outcome of the New Hampshire Primary predicts that President Barack Obama will win a second term in the November election, defeating Mitt Romney or any other Republican challenger by a comfortable margin.
This forecast comes from a statistical model of presidential elections (The PRIMARY MODEL) that uses primary performance as a major predictor of the presidential vote in the general election. In addition, the model relies on a cycle in presidential elections and adjusts for the partisan shift during the New Deal era. The model covers elections as far back as 1912, when presidential primaries were first used in large numbers. Since 1952, however, only the New Hampshire Primary is included.
Overshadowed by the intense Republican battle, Obama won the primary contest of his party in New Hampshire in commanding fashion. For the record, Obama captured 82 percent of the votes in the Democratic primary of that state, against token opponents. Any time a candidate of the party that controls the White House has gone unchallenged for renomination, the odds are overwhelmingly in favor of that candidate's victory in the November election. This goes back as far as 1912, when the incumbent president William Howard Taft first lost the primary battle and then the general election. Primary challenges to Truman (1952), Johnson (1968), Ford (1976), Carter (1980) and Bush (1992) augured poorly for them or their party in the general election.
The Primary Model allows for forecasts that pit Obama against each of the Republican contenders. The better their showing in the New Hampshire Primary, the stronger their showing against Obama in November. In the event that Mitt Romney, the winner of the Republican Primary in New Hampshire, goes on to be the party's nominee, Obama would defeat him by 53.2 to 46.8 percent of the two-party vote. In a race against Ron Paul, the second-place Republican finisher in New Hampshire, the Obama vote would go up to 56.9 percent. It would level off at 57.1 percent against Huntsman, Gingrich, Santorum or any other Republican.
While Romney did exceedingly well in New Hampshire for an out-party candidate in primaries, the showing in presidential primaries carries far more weight in the November election for the candidate of the party in the White House than it does for the candidate of the party out of the White House. Voters are known to base their ultimate decisions far more on what they think about incumbents than challengers.
Obama's reelection prospect is also aided by the cycle evident in president elections. As reported earlier, this alone puts Obama at 51.8 percent of the two-party vote. While that may be too close for comfort, primary performance puts him in a comfortable position to secure reelection. The likelihood of an Obama victory against Romney, given the vote forecast of the Primary Model, would be 0.88. And, given the forecasts for races against any other Republican, the likelihood would be near-certainty (0.99).
For the record, the Primary Model, with slight modifications, has predicted the winner of the popular vote in all presidential elections since it was introduced in 1996.