Single mothers are on the rise, making up roughly one in every four households with children under 18, according to a new study by the Pew Research Center . That growth, coupled with the overwhelmingly Democratic nature of single moms, provides another fascinating lens through which to view the changing demographics of the United States — and the challenges those changes pose for a Republican Party hoping to reclaim the White House in three years.

According to Pew, the increase in single mothers as a share of all families with kids under 18 comes largely from women who have never been married. In 1960, never-married single mothers accounted for fewer than 1 percent of all households with children under 18. By 2011, they constituted more than 11 percent of all homes with kids under 18, the study found. By contrast, the past 20 years or so have seen little movement among divorced, separated or widowed single mothers — who account for between 12 percent and 13 percent of the broader population of households with children under 18, according to Pew.

The increase in never-married mothers is even more evident when they are placed in the context of all single moms. They accounted for just 4 percent of all single mothers in 1960; now they account for 44 percent, the Pew study found. Women who were divorced, separated or widowed constituted 82 percent of all single mothers in 1960, but five decades later they make up just 50 percent of that group.

So what do these single moms — particularly the rapidly growing group of those who have never been married — look like?

Single mothers “overall are younger, black or Hispanic, and less likely to have a college degree,” according to Pew’s Wendy Wang, Kim Parker and Paul Taylor, who authored the study. Never-married single mothers are even younger (46 percent are under age 30) than single moms generally, and they are far more likely to be African American (40 percent) than the overall populace of single mothers, the authors found.

What do Pew’s findings mean for politics — especially at the presidential level?

Let’s start with the fact that single moms have been a solidly Democratic group in each of the past two presidential races. In 2008, then-Sen. Barack Obama won 74 percent of single moms — defined for these purposes as unmarried women living in households with children under 18. Obama followed that by winning 75 percent among that group in his contest with former Massachusetts governor Mitt Romney in November. In both of those elections, single moms constituted 6 percent of the overall electorate.

Of course, given the ethnic, racial and age overlaps among single mothers and groups — voters under 30, minorities, women — that backed President Obama (regardless of whether they had children), the fact that single mothers tend to be strongly Democratic should not be terribly surprising.

But dig further into the exit polling from 2012 and you see Obama heavily overperforming among single mothers across all demographic groups, not just those that tended to favor him in November.

Take white voters. Obama lost to Romney among white voters, 59 percent to 39 percent. But among white single mothers, Obama bested Romney 56 percent to 43 percent. Lower-income voters are another good example. Obama took 60 percent to Romney’s 38 percent in all households making $50,000 or less a year. Among under-$50,000 households that included a single mother, Obama took a whopping 79 percent to Romney’s 20 percent.

To be clear, the Republican Party’s issues with single mothers — as demonstrated above — are not its first priority when it comes to demographic problems that need to be solved before 2016. The first problem is clearly the GOP’s inability to win any significant share of the ever-increasing Hispanic population.

And it seems unlikely given the party’s losing margins among single mothers — and the increase in never-married women as a portion of the overall voting bloc — that Republicans will be winning majorities of single-mother voters anytime soon. But they also cannot afford to lose single mothers by such vast margins moving forward.

The rise of single mothers — and the Democratic dominance within that group — provides a window into the various demographic, messaging and, therefore, political problems that face Republicans as they seek to reinvent the party in hopes of reclaiming the White House in 2016. It’s not to be overlooked.