Democratic politicians like to decry what they describe as a widening economic gap in the nation. But the part of the nation where it is widening most visibly is their home turf, the place where they win their biggest margins (these metro areas voted 61% for John Kerry) and where, in exquisitely decorated Park Avenue apartments and Beverly Hills mansions with immigrant servants passing the hors d'oeuvres, they raise most of their money.

The bad news for them is that the Coastal Megalopolises grew only 4% in 2000-06, while the nation grew 6%. Coastal Megalopolitan states--New York, New Jersey, Massachusetts, Illinois--are projected to lose five House seats in the 2010 Census, while California, which has gained seats in every census since it was admitted to the Union in 1850, is projected to pick up none.

You see an entirely different picture in the 16 metro areas I call the Interior Boomtowns (none touches the Atlantic or Pacific coasts). Their population has grown 18% in six years. They've had considerable immigrant inflow, 4%, but with the exceptions of Dallas and Houston, this immigrant inflow has been dwarfed by a much larger domestic inflow--three million to 1.5 million overall.

Domestic inflow has been a whopping 19% in Las Vegas, 15% in the Inland Empire (California's Riverside and San Bernardino Counties, where much of the outflow from Los Angeles has gone), 13% in Orlando and Charlotte, 12% in Phoenix, 10% in Tampa, 9% in Jacksonville. Domestic inflow was over 200,000 in the Inland Empire, Phoenix, Atlanta, Las Vegas and Orlando. These are economic dynamos that are driving much of America's growth. There's much less economic polarization here than in the Coastal Megalopolises, and a higher percentage of traditional families: Natural increase (the excess of births over deaths) in the Interior Boomtowns is 6%, well above the 4% in the Coastal Megalopolises.

The nation's center of gravity is shifting: Dallas is now larger than San Francisco, Houston is now larger than Detroit, Atlanta is now larger than Boston, Charlotte is now larger than Milwaukee. State capitals that were just medium-sized cities dominated by government employees in the 1950s--Sacramento, Austin, Raleigh, Nashville, Richmond--are now booming centers of high-tech and other growing private-sector businesses. San Antonio has more domestic than immigrant inflow even though the border is only three hours' drive away. The Interior Boomtowns generated 38% of the nation's population growth in 2000-06...

Twenty years ago political analysts grasped the implications of the vast movement from Rust Belt to Sun Belt, a tilting of the table on balance toward Republicans; but with California leaning heavily to Democrats, that paradigm seems obsolete. What's now in store is a shifting of political weight from a small Rust Belt which leans Democratic and from the much larger Coastal Megalopolises, where both secular top earners and immigrant low earners vote heavily Democratic, toward the Interior Megalopolises, where most voters are private-sector religious Republicans but where significant immigrant populations lean to the Democrats. House seats and electoral votes will shift from New York, New Jersey and Illinois to Texas, Florida, Georgia, Arizona and Nevada; within California, House seats will shift from the Democratic coast to the Republican Inland Empire and Central Valley.

Demography is destiny.