Much of the Democrats’ continuing strength is based on an old formula: Battle to a draw in rural areas by using conservative cultural messages (Sen. Claire McCaskill made much of her support for a tough prayer amendment in August), then roll up big margins in St. Louis and Kansas City.

But the Democratic stranglehold on statewide offices could eventually give way, analysts said. Driving the trend: Missouri’s population pattern.

Big swaths of rural Missouri continue to gain population, a major reason why Republican strength has grown rapidly in the General Assembly. The state’s six-fastest growing counties — Christian, Lincoln, Pulaski, St. Charles, Taney and Warren — all went big for Romney in Tuesday’s election.

“All the population growth in the state is occurring in Republican areas. All of it,” said Missouri GOP consultant John Hancock.

While northern Missouri, which also is reliable Republican turf, has lost population in recent years, the fastest-growing counties have more than picked up the slack.

“The demographic changes to me are the most important thing,” said Missouri State University political scientist George Connor. “Missouri is going to remain red. And I don’t think pink. I think we’re going from medium-rare to rare.”

Meanwhile, the state’s Democratic base is increasingly isolated in the two big cities, making it tough for Democrats to gain ground in the General Assembly.

“It’s an issue of concentration,” said longtime Missouri Democratic operative Roy Temple. “There is clearly 50 percent of the vote in Missouri that’s accessible to Democrats. It’s just not distributed across the state equally.”

So far, he said, the state just hasn’t seen the same population trends that have boosted Democrats in other states.

Until the early part of this century, Democrats controlled the General Assembly for decades — often with huge majorities. Those party allegiances dated back to the Civil War, Hancock said.

“It took decades for that behavior to change and to drive itself down the ticket into state legislative races and the county courthouses,” he said.

Those majorities were comprised of conservative Democrats who kept Missouri a low-tax state. So it wasn’t much of a jump to the Republican House and Senate of today.

These days, Republicans head into statewide elections with a slight advantage in numbers, Hancock said. “Democrats produce such large margins out of the cities and ring counties that it creates tremendous pressure (on Republicans) to win everything else substantially.

“It’s a math problem that can work,” Hancock said, “but there’s no margin for error.”

That begins to explain why Republican candidates, such as U.S. Senate contender Todd Akin and gubernatorial nominee Dave Spence, struggled this year. Both made numerous mistakes that allowed Democrats to surge past them.

Kansas

Republican domination of Kansas politics grew on Election Day when the party increased its hold on the Kansas Legislature. All statewide offices are held by Republicans, as are all four congressional seats.

And the party, led by Gov. Sam Brownback, is expected to use its increasing dominance to approve more changes in tax policy and judicial selection, as well as cultural issues like abortion and school choice.