Presidential Home Field AdvantageJust thought I'd take a look at how presidential candidates have done in their home state as compared to how they did nationally. Criteria: I looked only at the elections since 1980, and I ignored third party candidates. Here are the results:
Year. Cand......State... HS......Nat..... Adv.
2004 Bush......Texas... 61.1% 50.7% 10.4%
2004 Kerry......Mass.... 61.9% 48.3% 13.7%
2000 Bush......Texas... 59.3% 47.9% 11.4%
2000 Gore......Tenn.... 47.3% 48.4% -1.1%
1996 Clinton.. Ark....... 53.7% 49.2% 4.5%
1996 Dole...... Kansas. 54.3% 40.7% 13.6%
1992 Clinton.. Ark....... 53.2% 43.0% 10.2%
1992 Bush..... Texas... 40.6% 37.5% 3.1%
1988 Bush..... Texas... 56.0% 53.4% 2.6%
1988 Dukakis. Mass.... 53.2% 45.7% 7.6%
1984 Reagan. Calif..... 57.5% 58.8% -1.3%
1984 Mondale Minn.... 49.7% 40.6% 9.2%
1980 Reagan. Calif..... 52.7% 50.8% 1.9%
1980 Carter... Georgia 55.8% 41.0% 14.8%
Average..........................54.0% 46.8% 7.2%
In 2004, President Bush got 61.1% of the vote of his home state of Texas, and 50.7% of the national vote, so his home field advantage is 10.4%. Overall, the candidates averaged 7.2 percentage points better in their home states than they did nationally.
It will come as no surprise to anybody paying attention that Al Gore did worse in his home state of Tennessee than he did nationally, but how many would have guessed that the only other recent, major party presidential candidate to underperform with his home staters was Ronald Reagan in 1984?
Problems with the study? Well, there is the issue of whether the margin shown represents a home state advantage, or if it just represents the propensity for Democratic candidates to come from liberal states, and Republican candidates to come from conservative ones. Kerry and Dukakis didn't solely do better in Massachusetts than elsewhere because they were Bay Staters; Al Gore got 59.8% of the Massachusetts voters without a home field advantage. Ditto with Bob Dole. His 54.3% in Kansas in 1996 compares unfavorably with President Bush's 58.0% in 2000 and 62.0% in 2004. But of course, there were many other changes between the 1996 and 2000/2004 elections.
Overall I'd suspect that the true home state advantage is not a lot less than 7.2%; 5% seems like a reasonable estimate.