The biggest credit card companies are trying to get Donnice Polk, a 70-year-old therapist in Shawnee, Okla., to spend more with plastic money.

She's been getting offers from Capital One ( COF) in the mail almost every month. American Express ( AXP) has sent her similar letters a couple of times in the past six months. Even after having gone through a foreclosure in July 2007, she continues to routinely get credit card offers telling her she's qualified.

"I just threw away three last week," Polk says. She began using credit cards heavily around age 55.

The credit crunch engulfing the U.S. economy, in some ways, has missed some pockets of society. When market research company Mintel surveyed more than 3,000 consumers, 1,000 businesses and 1,000 email users about credit card offers received in the mail during the third quarter, it estimated nearly 55% of 1.507 billion offers sent to non-customers went to people 50 and over. The data clearly show that the 50-and-over crowd has been getting the most solicitations for several years.

"The boomers are still a major economic presence in the marketplace," says Dennis Moroney, research director in bank cards at research and advisory firm TowerGroup. He says the older generations are more likely to repay debts, which means lower profits but also reduced risk. "Right now the banks are looking for any good customers, and the elderly would be the ones who fall into that bracket."

Card companies might have more reason to seek out business with the boomers. Curtis Arnold, founder of U.S. Citizens for Fair Credit Card Terms, which is associated with the Web site CardRatings.com, says the first credit cards came out in the 1950s, when recent retirees grew up. "Seniors still have a lot more of a savings mentality than the average twenty-something, but the savings mentality has been gradually waning in our society as a whole," Arnold says.

Many credit card companies manage to reach older people without necessarily aiming for them. For example, home improvement retailer Lowe's ( LOW) sent an offer to Marti Denniso in North Little Rock, Ark., even though the 73-year-old doesn't leave her house to do much besides grocery shopping.

The teenage friend of a friend who was working at a local Lowe's store called Denniso to see if she'd sign up for a card issued by GE Money Bank, a unit of General Electric ( GE). Lowe's had promised its employees they'd get $100 for persuading five acquaintances to apply. "I didn't end up doing it, but I was willing to help her some," Denniso says. She found a couple other people who were willing to apply for the card instead. (Denniso's name was altered to protect her identity for this story.)

Lowe's media relations department didn't respond to a request for an interview. GE didn't provide an interview before the time of publication.

"We don't really target in terms of demographics or age, but we always want high quality," says Mona Hamouly, a spokeswoman at American Express. She says her company seeks out high-spending, affluent card members. "Boomers tend to have that discretionary income and meet the criteria we look for. They're an important group to us."

Hamouly declined to provide statistics about the demographics of American Express customers. The company has offered a "Gold Senior Member Card" for many years that includes perks such as travel benefits, which people in retirement tend to have more time to use. About 55% of American Express' direct mail in the third quarter went to people 50 and over, according to Mintel's estimates, in contrast with 60% for Chase Card Services, a unit of JPMorgan ( JPM), and 58% for Capital One. Some 45% of Citigroup's ( C) Citibank mail solicitations went to people in that age group.

Linda Sherry, director of national priorities at the nonprofit Consumer Action, says she's in the 50-plus demographic and has noticed that Capital One continues to send her credit card offers in the mail despite the credit crunch. Her advice for others who might also be receiving such offers is that they not respond on a whim.

"If you carry a card that keeps hitting you with late fees or doing something that's annoying you, you might legitimately look for a new card. But you shouldn't look for a new one every second," Sherry says.

Sonja Ryst has previously worked as a staff reporter at BusinessWeek.com and Dow Jones Newswires. She's also freelanced for publications including The Wall Street Journal. She graduated from Stanford University with honors.

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