When she was still single in her 40s, Debra Siegel made a list of qualities for her yet-elusive perfect husband: honest, family-oriented, a hard worker and physically fit.

But the years passed and the list went unfulfilled.

"When I hit 50, the bells went off," she says. "I didn't want to be alone for the rest of my life."

That's when she took what she calls "drastic action."

Her future husband, Dan Furlin, was of a similar mind.

"I didn't think marriage was in the picture for me," he says. "Once you hit 50, you don't want to go through the rest of life without your soul mate. I was a little bit more aggressive."

Both went the online dating route and met within months. The Dunedin, Fla., couple are both fitness-conscious and vegetarian. They were also both natives of New York state, and each had lived in Los Angeles. They moved to Florida before meeting online, and married in 2003.

Siegel-Furlin, 56, and Furlin, 58, are among a small but growing group of older adults marrying for the first time after age 45.

Years ago, these older singles would have been known as the "spinster" neighbor or the confirmed "bachelor" friend. But now, longer life spans mean 50 is the new 30 — there's plenty of life ahead.

That, coupled with the baby boomer "never-wanna-be-old" attitude and a greater number of aging singles in the population, makes it more likely that those who want to marry actually will.

An analysis of Census records of Americans ages 45 to 55 shows that the percentage of those who said they had never been married in 2006 had doubled since 1990, and the percentage of those who were currently married had dropped by 9 percent.

It's fairly difficult to get a real handle on this segment of the singles population because no federal entity tracks first marriages at specific ages. The closest count is the median age at first marriage, which in 2006 (the latest year for which data are available) was at its highest point: men at 27.5 and women at 25.5, according to the U.S. Census.

A tally by the Centers for Disease Control and Prevention, which is available just for a 20-year period, 1970 to 1990, shows that in 1990, only 0.4 percent of women and 0.6 percent of men married for the first time at ages 45 to 49.

According to the most recent data from the federal Survey of Income and Program Participation, which includes marriage, 13 percent of those who wed in 2003 were 45 and older.

THANKS TO INTERNET

Internet dating has largely made it possible for many of these later-life first marriages. It's only in recent years that some sites have started monitoring that demographic. Among them is Yahoo Personals, based in Santa Clara, Calif., which reports a 33 percent increase from January 2006 to November 2007 among users ages 45 and over who say they have never been married. Since 2005, Match.com reports an increase of almost 10 percent of new members 45 and older and who have never been married; these now make up almost 14 percent of its members.

"As people get older, they tend to find themselves in fairly established patterns, so the ability to meet new people goes down over time. They've got to do something new if they want to meet different people," says Craig Wax of Dallas, senior vice president and general manager for Match.com for North America.

Brian Lebowitz, 57, and Lise Goldman, 53, are to be married June 22. They met online almost two years ago and found out at the time that they lived within blocks of each other. Lebowitz, an attorney, lives in Washington, D.C. Goldman, who works in economic development, now lives in suburban Chevy Chase, Md. Lebowitz says his job and his hobby as a book collector took up most of his free time. But when he turned 55, he decided to give online dating a shot.

"I'd pretty much given up, but then thought I would give it a try and see what it was like," he says. "Some people — myself included — would be more comfortable starting off communication by e-mail rather than going up to somebody at a party. It's a less threatening way to go about it."

Goldman says she always wanted to be married. She had been engaged twice — once in her mid-20s and again more than a decade ago — but she says it just wasn't right until she met Lebowitz, whom she says is intelligent and kindhearted.

"There are wonderful people still out there who are hiding away in their work," she says. "He's an international lawyer, so he needs to work evenings a lot. That's been one of the blessings that kept him away from the dating scene."

Dating Web sites have been reinventing themselves since online dating took off in the mid-1990s. They've refined their methods, largely emphasizing a more scientific approach, which often includes compatibility and personality testing. Others have focused on niche marketing, including Spark Networks, whose online dating sites include JDate for Jewish singles, as well as www.CatholicMingle.com, www.InterracialSingles.net, www.BlackSingles.com, www.LatinSinglesConnection.com and PrimeSingles.net. That site, as well as lavalifePRIME and www.BOOMj.com, is among those offering social networking for these older singles.

LavalifePRIME surveyed 1,001 adults ages 45 to 65 in the U.S. and Canada last month who are not in a serious relationship and found almost one-third (31 percent) have never been married.

Carl Weisman of Redondo Beach, Calif., author of "So Why Have You Never Been Married?," conducted an online survey for the book and found that 48 percent of the 1,533 bachelors ages 40 and older who responded said they were afraid of marrying the wrong person.

"They'd rather go to the grave unmarried than marry someone wrong," says Weisman, 49. "The No. 1 fear is marrying the wrong person — more than not marrying at all — by 10 to 1."

In addition to the online survey, Weisman conducted lengthy telephone interviews with 30 men. He says writing the book changed his own perspective.

"I was interviewing men 10 years older than me, and I felt like I could look into my future. I was not necessarily afraid, but I realized if I didn't change things, it was not going to change," he says.

Just weeks after completing the book, Weisman says he met a woman at a wine-tasting event and they now live together. They've talked about marriage; by the time they tie the knot, he expects they will have known each other three years.

Pepper Schwartz, a sociologist at the University of Washington in Seattle who developed a personality test for www.Perfectmatch.com, says the Internet has given never-marrieds new hope for matrimony.