It’s all about demographics now....not so much about the economy anymore. Romney actually won a higher percentage of the white vote in 2012 than Ronald Reagan won in 1980, meaning that if demographics had not changed dramatically since 1980, Romney would have won in an even greater landslide that Reagan did that year (he only lost six states).
From the Washington Examiner
. In 1980, Reagan won white voters 56 percent to 36 percent, with third party candidate John Anderson taking 8 percent of the vote. He ended up beating Carter by 10 points and winning 44 states.
Romney wins white vote by same margin as Reagan did in 1980 landslide
Actually, John Anderson, a Republican who lost to Reagan in the primaries of 1980, won 8% of the vote in the general election. Most of his vote would likely have gone to Reagan so those percentage comparisons with Romney don't work from 1980 to 2012.
The Republicans are losing elections because many conservatives, mostly whites, are staying home because they're tired of their priorities being ignored.