The Linguistic Society of America recently selected "red state, blue state, purple state" as the phrase that most dominated national discourse in 2004. Behind this color code of American voting -- red states favoring Republicans, blue states favoring Democrats and purple states undecided -- are several trends that should trouble Democrats.

In November's election, according to a Los Angeles Times analysis, President Bush carried 97 of the nation's 100 fastest-growing counties, most of them "exurban" communities on the periphery of metropolitan areas. These counties grew by more than 16 percent from April 2000 to July 2003, and gave Bush a 1.72-million-vote advantage over Sen. John Kerry, almost half the president's total margin of victory.

More troubling for Democrats is that more than 80 percent of these high-growth countries are in red states that Bush won twice. And with each presidential election since 1996, these counties yielded increasingly more net votes for Republicans. At the state level, things are no better for Democrats.

New Census Bureau numbers show that the 10 fastest-growing states -- from No. 1 Nevada to No. 10 New Mexico -- are in the West and the South. Bush won nine of them in November. This population growth helped the red states gain seven Electoral College votes after the 2000 census, and will drive more gains after the 2010 reapportionment since demographers agree these places are gaining popularity. But the Democrats' biggest headache emerges when looking at who is moving and why.

Growing red-state counties are filling up more with families starting out than with those who have reached their earnings peak. These young people are seeking economic freedom, entrepreneurship and growing job opportunities, confirming a recent Pacific Research Institute report.

The U.S. Economic Freedom Index shows that people are fleeing less economically free states to live in freer states. The net domestic migration rate was up 19 people per 1,000 for the 20 freest states but down a dismal 16 people per 1,000 for the 20 least-free states. New York and California experienced the largest net loss of domestic residents during 2003-04. They also have the least economic freedom. The study ranked states based on how friendly or unfriendly their state government policies are toward free enterprise and consumer choice.

The Great Plains and Rocky Mountain states are most economically free. The Northeast (excluding New Hampshire), Midwest (excluding Indiana) and California are least free. The economic freedom map is strikingly similar to the red-blue map. In other words, differences in economic and political philosophy regarding the role and scope of government, often translated into actual policies, are driving relocation and voting decisions. This is very fundamental and should worry Democrats.

In November, 23 of the 25 freest states voted for Bush. In stark contrast, 17 of the 25 least-free states voted for Kerry. In the long term, the differences in economic freedom will magnify this partisan divide as people continue the move to freer states and take their Electoral College votes with them.

Economic freedom explains the red-blue map without reference to moral or cultural issues. As the folks from the administration of former President Clinton would say: "It's economic freedom, stupid." Since state and local economic policies are slow to change, this represents a serious, structural problem for Democrats -- even if they comprehended the root problem, which they don't.

As freedom lovers emigrate, Democrats will have to squeeze ever more votes from shrinking urban centers and inner suburbs. Republicans will dominate the counties and states exploding in population due to their greater economic freedom. Democratic strategists would be wise to push economic-freedom reforms to make their party more competitive.