1
Portions of the paper have appeared in PS: Political Science & Politics, 2004. For an excellent overview of forecast
models of presidential elections, see Jones 2002, as well as Lewis-Beck and Rice 1992, and Campbell and Garand 2000. For
forecasts in 2004, see PS: Political Science & Politics, Oct. 2004, and Jan. 2005.
2
The elections of 1952 and 1968 rely on the primary vote received by sitting presidents (Truman and Johnson, respectively)
who later withdrew from the race. The ultimate nominees (Stevenson and Humphrey, respectively) did not compete in
primaries.
3
The support for “rival” in Table 1 refers to the primary vote received by whatever rival candidate for the nomination was
in second or first place in primary voting, depending on whether the nominee was the primary winner. In a few cases rival
support refers to the “uncommitted” category or the sum of all other candidates.
4
For the 1912 election, the two-party vote was approximated through a regression of the congressional vote on the
presidential vote. The intrusion of Teddy Roosevelt’s third-party campaign was so severe that the Republican candidate
ended up in third place with only 23.2% of the total popular vote while Wilson, the Democrat, won with 41.8%. Using a
regression of the House vote on the presidential vote in the 10 elections preceding and following the 1912 case (1872-1952),
I derived an estimate of the two-party Republican vote in the 1912 presidential election (56.3%) that was used in this
analysis. Note that the correlation between the two-party vote for president and House in that period was extremely high (.
95).
5
The inversion was done around the means of the variables: 60.0 for incumbent-party candidates who were sitting
presidents; 55.6 for other incumbent-party candidates; and 47.1 for out-party candidates.
6
6
The measure for the Republican candidate is inverted (-1) because the Democratic vote is used as the dependent variable.
Note that there is no need to include the partisan adjustment in the prediction equation since this variable is scored 0 for all
post-1932 elections.
7
It is by no means certain that Kennedy won the popular vote. The format of the presidential ballot in Alabama makes it
nearly impossible to determine the popular vote for Kennedy and Nixon in that state. Alabama voters were able to vote for
each of the 11 electors separately rather than cast a single vote for a whole slate of partisan electors. Of the 11 Democratic
electors, five ran as pledged to support the official Democratic nominee (Kennedy) in the electoral college, while the other
six ran as “free” electors and wound up voting for Harry F. Byrd in the electoral college. The “official” count of the popular
vote for Alabama lists the votes received by the top Democratic elector—a free elector, who voted for Byrd, not Kennedy,
in the electoral college. Given all these complications, it might seem justified to award Kennedy no more than 5/11 of the
average vote cast for Democratic electors in Alabama (the share of pledged electors). In that event, Nixon wins the national
popular vote in 1960. See Gaines (2001).
8
The close fit of the current forecast model for 2000 is especially pleasing since the earlier version used for an advance
forecast in 2000 overstated the Gore vote by nearly two standard errors. The switch from a win-lose measure of primary
support to one relying on relative strength, albeit with constraints, appears to have paid off.
Convention