Election graphic: How states have shifted over the decades

As Goes Ohio

Ohio, which has voted for the winner in every election since 1964, provided the decisive electoral votes in 2004, and it is the state likeliest to play that role again this year, according to the FiveThirtyEight model.

Incumbent Stability

When an incumbent runs for re-election, fewer states typically change party affiliation: only three states shifted from 2000 to 2004, and five from 1992 to 1996. Yet incumbency is no guarantee of victory. Bill Clinton defeated the first President George Bush by winning 22 previously Republican states.

Newly “Safe”

Although now labeled a “safe” Democratic state, New Jersey was once considered a swing state. California, now another “safe” Democratic state, voted Republican in nine out of ten elections from 1952 to 1988.