Having a base that is increasingly white, rural and old doesn’t sound like a winning formula for the demographically challenged Republican Party.

Whites made up 95 percent of the electorate in 1952 but are now below three-quarters. Need proof of their (I should say, our) declining clout? John McCain beat Barack Obama last year among white voters, even as Obama improved on the Democratic showing among them.

A few weeks back, Nate Silver at Fivethirtyeight.com noted that Gallup polling shows that 89 percent of self-identifying Republicans are white, compared with 65 percent of Democrats. That’s roughly how things broke down in the voting last year.

Consider this remarkable statistic. In 1980, 32 percent of the electorate consisted of white Democrats (or at least white Carter voters.)

Likewise, in 2008, 32 percent of the electorate consisted of white Obama voters.

But in 1980, just 9 percent of the electorate were nonwhite Carter voters, while 21 percent of the electorate were nonwhite Obama voters last year.

Over at Huffington Post, Thomas B. Edsall writes about how the GOP’s “white voter strategy” is “running out of gas.” Edsall cites polling data suggesting that the GOP’s anti-Obama messages have helped drive down his support among whites, but argues this is a conservative message that fails to appeal to minorities will continue to wound the party.

The Republican Party thrived between 1968 and 2000 primarily because of the gains it made among white voters, especially among formerly Democratic working-class whites, a disproportionate share of whom were men. By 2000, however, the white percentage of the electorate dropped to 80 percent and below.

The trend is striking. In 1976, 89 percent of the electorate was white. That number fell every four years, to 88 percent in 1980, 86 percent in 1984, 85 percent in 1988, 83 percent in 1996, 81 percent in 2000, 77 percent in 2004, and 74 percent last year. The only exception was 1992, when the presence of independent candidate Ross Perot drove the white percentage of the electorate up to 87 percent.

But that’s not the whole picture.

There are two gubernatorial contests this year, and Republicans are definitely the better bet in both states. For Democrats to come out ahead either in Virginia or New Jersey would require a major change in the dynamics of either race.

The GOP is also doing quite well at the legislative level.

Nearly every week, I get an e-mail from the Republican State Leadership Committee touting a win in a special legislative election. Republicans have won 15 of those since November.