Greater Minnesota feels left behind. That's the headline version of the story that was reported one year ago in the wake of a state House election that produced a partisan map more divided between urban and rural regions than any in modern memory, as Republicans took a 72-62 majority.

Politicians have quibbled in the ensuing year over whether voters' rejection of DFL incumbents in 10 Greater Minnesota districts — and inner-ring suburban voters' spurn of Republican candidates — was deserved. But about this, there can be little disagreement: Metro and Greater Minnesotans have grown apart in recent decades in important ways — age, income, educational attainment, race and culture. Those trends are persistent; some may be accelerating. And those trends are complicating Minnesota's 157-year-old project in democratic self-governance.

Today and for the next two Sundays, Opinion Exchange will examine the state of Minnesota's internal union, past, present and future. It's not a disinterested look. The Star Tribune has long held that Minnesotans' willingness to function as "one state" — to aggregate their resources, pursue shared goals and provide public services at the state rather than local level — has been a key contributor to the prosperity and quality of life they enjoy.

Our view is that no part of Minnesota should be left behind. No part of Minnesota can reach its full potential unless the whole state does. And all of Minnesota would benefit from a narrower urban/rural divide.

Narrowing that gap must start with an understanding of what separates the two populations and what does not. Much has been made of the income gap between the two regions. The median household income gap is wide: nearly $14,000 in 2013, the last year for which data is available.

But nearly as large is the difference in cost of living between the metro area and many places in Greater Minnesota. Lower housing costs outstate compensate in many places for the difference in average wages, according to the state Department of Employment and Economic Development (DEED). For example, by DEED's calculus, providing basic necessities for a family of two adults and one child requires an annual income of $55,845 in Hennepin County, compared with $42,065 in Blue Earth County — another nearly $14,000 gap.

To be sure, median figures mask substantial variations from community to community. Some Greater Minnesota residents likely have good reason to resent their low salaries compared with what comparable work pays in the Twin Cities.

But a wide disparity between metro and Greater Minnesota incomes is not new. The gap was at its narrowest in the late 1960s, grew wider in the 1970s and has been a fact of Minnesota life ever since. In fact, the difference in median household incomes between the seven-county metro area and the state's other 80 counties is narrower today in inflation-adjusted dollars than it was a decade ago. The reason: Metro incomes fell more sharply during the Great Recession than did incomes in the rest of the state, where agriculture served as a financial stabilizer during the downturn.

If income and standard of living aren't the story, what is? Consider other demographic trends:

• The last U.S. Census in which Greater Minnesota's population was larger than that of the seven-county metro area was in 1980. Since then, the rate of growth in the Twin Cities has outstripped that of the rest of the state; since 2010, total growth outside the metro area has come to a near halt. About 55 percent of Minnesotans live in the seven-county metro area today.

• While population growth has stalled outstate, aging has not. Greater Minnesotans are markedly grayer than metro Minnesotans. In 36 of the state's 87 counties, more than one resident in five is a senior citizen, 65 or older. In 57 counties, the median age is past 40, compared with a Twin Cities median age of 36.6. Some Greater Minnesota counties are home to more people in their 70s than in their 40s.

• A striking educational attainment gap has developed between Greater Minnesota and the Twin Cities. In every metro county but Anoka, two of every five residents older than 25 have earned at least a bachelor's degree. Among Greater Minnesota counties, only Olmsted County, which includes Rochester, and Cook County in northeastern Minnesota are in that educational league. In half of the state's counties, fewer than 20 percent of the adult population have a four-year college degree.

Those phenomena are combining to produce a shortage of skilled workers in Greater Minnesota that's forecast to worsen with the retirement of the baby boomer generation, whose members are now between the ages of 51 and 69. Already, a difference in workforce size and strength is evident in the disparity between metro and outstate job vacancy rates — 4.6 percent in Greater Minnesota in this year's second quarter, compared with 3.2 percent in the seven-county metro area.

In many respects, the Greater Minnesota worker shortage is but a foretaste of trends that are projected to sweep the entire state in coming years. But the metro area has proved to be a stronger magnet for talent from other places — including other countries — than Greater Minnesota. For example, nearly 40 percent of Ramsey County residents were born outside Minnesota. In many outstate counties, that share is below 25 percent.

One result is a widening difference in the state's racial composition. Last year, one in four Twin Cities area residents was nonwhite, compared with one in 10 in Greater Minnesota. As recently as 1990, the nonwhite share of the population was in single digits in both regions.

Another possibly related difference can be seen in membership in a religious organization, which is much higher in western and southern Minnesota than in the metro area and the northeastern counties.

That underscores this point: The demographic differences that have developed around the state have consequences that are cultural and political as well as economic. Together, they are working as a wedge dividing city and country Minnesotans into unlike-minded and increasingly hostile camps on social and political issues. Witness the results of the 2012 ballot question on same-sex marriage: In Hennepin County, 64.7 percent voted no; in Cottonwood County in southwestern Minnesota (and quite a few just like it), the no vote was under 30 percent.

Can a people this divided still come to agreement via their elected representatives about how best to provide a foundation for border-to-border prosperity and a decent life for all? They must, or the Minnesota success story will be a closed book. In coming weeks, we'll describe how Gov. Mark Dayton and the Legislature might forge an agenda that strengthens the ties that bind Minnesota as one state.