Voting Power in the Electoral College: The Noncompetitive States Count, Too

Saturday, 15 February 2014
Grand Ballroom B (Hyatt Regency Chicago)
Steven J. Brams , New York University, New York, NY
In U.S. presidential elections, it seems, voters who do not live in competitive states, in which
either major-party candidate might win, do not count, because as individuals they cannot
influence the outcome in their states. Therefore, it would appear, they have zero voting power, as
measured, for example, by the Banzhaf index of voting power.

But noncompetitive states do influence the outcome, because their electoral votes are essential to
a candidate's victory. We resolve the paradox of how a noncompetitive state can influence the
outcome, even though its voters have no voting power, by showing how their votes in these states
set up the contest in the competitive states.

In the 2012 election, for example, the nine states considered competitive collectively had 110 of
the 538 electoral votes. But the contest gave Barack Obama a big head start, because he needed
only 33 of the 110 electoral votes to win, whereas Mitt Romney needed 79. This is because,
going into the election, the 42 noncompetitive states (counting Washington, DC, as one) gave
Obama a lead over Romney of 237 to 191 electoral votes, so there were many more ways that
Obama could win a majority of 270 electoral votes than Romney could.

In many of Obama's winning coalitions, no competitive state – including the largest, Florida –
could change the outcome by changing its vote, whereas this was not the case in almost all
Romney's winning coalitions, making them much more vulnerable. We measure the power of the
noncompetitive states, especially for Obama, by his relative likelihood of winning, as well as the
relative invulnerability of his winning coalitions, which can be attributed to the lead he enjoyed
in these states. Thus, the noncompetitive states count, but they exercise power in a different way
from the competitive states.