There's a lot of talk about the sorry state of the institution of marriage in America — among opponents of same-sex marriage, for example — and the data generally backs that up.

The marriage rate in the U.S. has plummeted to 51 percent of adults in 2011, from 72 percent in 1960. And new Census statistics show that that 36 percent of births in 2011 were to unwed mothers, a rate that jumps to 62 percent for women 20 to 24, 68 percent for black women, and 57 percent for women with less than a high school diploma.

But things could be worse. Andriana Bellou, a Greek economist at the University of Montreal, suggests in a new research paper that U.S. marriage rates are 13 percent to 30 percent higher than they'd be without the internet. This isn't entirely unexpected, says Brenda Cronin at The Wall Street Journal. "Previous studies have suggested a correlation between the internet and the marriage market." But Bellou's study goes a step further, "providing 'pretty convincing' evidence 'that it's a causal effect.'"

Bellou's "fascinating study" charts marriage rates among Americans age 21 to 30 on a map of the uneven geographic expansion of broadband internet, says Kevin Drum at Mother Jones. When high-speed internet took off in an area, marriage rates jumped. She looked at several non-causal explanations for this relationship. Drum notes a few of them:

Maybe tech-friendly places have always produced higher marriage rates. Or maybe sociable people like the internet and also like getting married. Or it could be that causality runs in the other direction: Maybe people who are more likely to get married are also more likely to move to tech-friendly places. Etc. [Mother Jones]

But those explanations didn't make sense. Based on earlier, pre-broadband marriage rates, there is nothing especially nuptial-friendly about the areas with high adoption of high-speed internet. Bellou's conclusion, says Drum, is that "other things equal, better access to the internet really does produce a greater number of marriages. eHarmony really does work."

That's actually "the basic intuition here," says Brad Plumer at The Washington Post. "Stuff like online dating makes it easier for people to find potential partners." And that explanation is "not utterly implausible." Online dating is becoming more widely accepted — even Martha Stewart is doing it! — as people start to rely on the web instead of friends and family for everything from advice to meeting people. Besides, "researchers have already noted that the internet allows us to find jobs and homes more easily," says Plumer. "Why not spouses?"

But while this is good news for marriage, it isn't necessarily great news, Bellou tells The Wall Street Journal:

If the internet indeed makes meeting people easier at all times and ages then one might consider entering a marriage less thoughtfully to begin with.... This would imply more marriages and remarriages but also more divorces. If, on the other hand, the internet allows matching between more compatible people, one would expect divorce rates to decrease. More research is required to disentangle these effects. [Wall Street Journal]

That's only one reason to "file this under 'not conclusive, but certainly fascinating,'" says the Post's Plumer. The other is that Bellou doesn't conclusively prove cause-and-effect. More research will be needed to bear out her findings. But "it's an intriguing theory." Marriage rates really are dropping fast, he adds, and "it's possible that the internet's pushing against the tide, at least on the margins."