A decline in the number of white voters and a surge in voters from ethnic minorities and women helped Obama on election night. Ohio, one of the key battleground states, was captured in part through a rise in turnout among African-Americans, who voted overwhelmingly for Obama.
Back in August, Graham had said: "The demographics race we're losing badly. We're not generating enough angry white guys to stay in business for the long term."
This year is likely to be the first in recent history when the majority of babies born in the U.S. are born to families from an "ethnic minority" background. That demographic shift is already being felt at polling stations – 72 percent of those who cast their vote this year were white, down from 74 percent in 2008, according to exit polls by the Associated Press. The Republican Party's dominance of the white vote has persisted since President Richard Nixon won the votes of white voters in the Southern U.S. through the 'Southern Strategy.'
The Republican Party has tried to make the point that it is not just the party of white voters, via high-profile speeches at the GOP convention from Republicans of an ethnic minority background, but early signs are that it has failed to convert voters.
Racial minorities made up 45 percent of those who voted for Obama, and he made gains among Hispanic and Asian-American voters this time round, according to AP exit polls. His strength with Hispanic voters, who made up an estimated 10 percent of all votes cast this year, up from 9 percent in 2008, is particularly striking, with 71 percent of the Hispanic vote to Romney's 27 percent.
In contrast, Romney had a 20 percentage point lead in the white vote.
Women voters have also been turned off by a number of high-profile misfires on the subject of rape and abortion. Two Republicans, Todd Akin and Richard Mourdock, lost out in their race to become Senators on Tuesday. Akin had claimed that women couldn't get pregnant from "legitimate rape," though he later backtracked on those comments. Mourdock had said that pregnancy resulting from rape was "something God intends to happen."
But repudiation of those remarks didn't stop them from lingering. Exit polls from the AP suggested that Obama led by 11 percentage points in the female vote.
Written by Catherine Boyle, CNBC. Twitter: @cboylecnbc.