Households in which children are being raised by both of their married biological parents are most common in the Mountain West, parts of the Midwest, and the Northeast.
They are least common in New Mexico, Oklahoma, and the Deep South, according to a new analysis of census data by W. Bradford Wilcox, a University of Virginia sociologist, and Nicholas Zill, a psychologist.
"These patterns are important because evidence suggests that children usually benefit from growing up with two parents," noted David Leonhardt in an article on the analysis for The New York Times.
"It's probably not a coincidence, for instance, that the states with more two-parent families also have higher rates of upward mobility."
That Utah has the highest percentage of children living with two married biological parents agrees with Pew Research Center findings disclosed by the Insider Report last month, showing that Mormons are far more likely to marry than members of other major religious groups in the United States. Of Utah's 2.9 million population, 2 million are Mormons.
The second highest percentage is in Minnesota, 56 percent, followed by Nebraska (55 percent), New Jersey (54 percent), New Hampshire and North Dakota (both 53 percent), Massachusetts (52 percent), and Connecticut, Iowa, and Idaho (all 51 percent).
The percentages include only households with two married biological parents and exclude households with one parent and a partner who is not the child's biological parent, households with two unwed biological parents, households with adopted children, and households with same-sex couples.
After Mississippi's 32 percent, the states with the lowest percentages are Louisiana (36 percent), Arkansas (37 percent), Alabama (38 percent), New Mexico, Nevada, Georgia, South Carolina, and Oklahoma (all 39 percent), and Tennessee (40 percent).
Wilcox and Zill maintain that there are two models for having a large percentage of stable families with two biological parents.
In the blue-state model, Americans get more education and earn higher income, and better-educated, higher-earning people are more likely to marry and stay married.
In the red-state model, educational levels are closer to average but "residents are more likely to have deep normative and religious commitments to marriage and to raising children within marriage," Wilcox and Zill write in a paper for the Institute for Family Studies.
The lowest percentages of two-parent families tend to be in red states with the lowest levels of education, and in blue states with only average levels.