More than twice as many couples who married last year met through online dating services than at a club or social event, according to a new survey commissioned by Match.com.

The survey found that 17 percent of those who married in the past three years met online, making it the third-most-frequent method of introduction, behind meeting through a mutual acquaintance or at work or school.

The study, conducted by the research firm Chadwick Martin Bailey, shows how quickly online dating — in existence for less than two decades — has revolutionized the way people find and pursue potential mates.

“It does seem to have displaced all other forms of dating,” says Susan Frohlick, a cultural anthropologist at the University of Manitoba who has studied online dating. “I would say that it’s been in the last five years that it’s become hyper-mainstream.”

Online dating statistics have always been hazy and are frequently contradictory. The Match.com-sponsored survey, for instance, found that 15 percent of couples married in 2006 met through online dating sites, but a 2007 Harris Interactive poll sponsored by eHarmony found that 6 percent of couples married the previous year met online. (The Harris study claims that 2 percent of recently married American couples met through eHarmony.)