In what may be the genesis of a trend that could reach the comfy spas of Napa Valley, 140 massage therapists and other spa workers at the elegant Claremont Resort and Spa here are trying to form a union.

The hotel, an 87-year-old landmark that straddles the border of Oakland and Berkeley, is resisting the effort. But that has prodded politicians in both cities to get involved on the side of the employees.

The dispute, though, could have broader implications for the spa industry, which exploded in the last decade. As more people sought relief from aches and pains, hotel chains and smaller operations opened spas to serve that demand.

“It could certainly spread to Napa Valley,” Katie Quan, a labor policy specialist at the Institute of Industrial Relations at the University of California, Berkeley, said of the unionizing effort at the Claremont Spa. “It’s an area that I think is probably ripe for organizing because the (profit) margin on spas is probably high enough to support union wages.”

According to spa workers at the Claremont Hotel, discontent has brewed for much of the 1990s over wages, benefits and conditions. The anger boiled four years ago when KSL Recreation Corp., a unit of KKR & Co., bought the hotel, required the spa workers to reapply for their jobs at lower pay, and fired several older masseuses.

The masseuses sued for age discrimination, and the case was settled out of court.

Many of the hotel’s other workers are unionized through Local 2850 of the Hotel Employees and Restaurant Employees International Union.

But the spa employees are not, and thus do not receive health care benefits unless they work at least 32 hours a week, they said.

Rarely are they scheduled to perform that many massages per week, the workers contended. Further, providing many more therapies than that in a week can lead to serious muscle, tendon and other related disorders, they added.

“You end up injuring yourself,” said Meheret Fikre-Sellasie, 43, a massage therapist at the spa for the last 18 months.

Spa workers also are seeking better basic pay, now pegged at $6.75 an hour, and a larger cut of massage fees, which can range as high as $152 for 80 minutes.

“Claremont is pretty much charging ... the highest rates in the area, and pays their therapists the lowest,” said Olaf Fischer, 47, a massage therapist there for about a year.

Further, therapist Leslie Fitzgerald said she and her co-workers want what the hotel’s unionized employees get - better health care benefits that kick in at 20 hours a week, and job security. She recalled that no union workers were fired when KSL took over.

“That made a big impression on me,” said Fitzgerald, a therapist at Claremont for seven years. “I’m still angry at how they treated us, and it hasn’t gotten any better.”

The Claremont’s view of the situation is much different. Marketing director Denise Chapman said the spa workers would be “better off continuing to communicate directly with us without a third party intervening.”

The spa’s wages and benefits are comparable to those at other spas in the area, she added.

Chapman said the hotel supports the right of the workers to seek a union election. “We’re strongly committed to preserving the standard process for unionization,” she said.

But that is a sticking point. Stephanie Ruby, secretary-treasurer of Local 2850, said the union in December presented hotel managers with cards signed by spa workers indicating their desire for Local 2850 to represent them - a move that can be used in lieu of an election if both parties agree.

But management has refused to accept the cards, Ruby said, even though the hotel accepted similar cards for a group of hotel workers early last year, which resulted in contract talks and a good agreement.

The spa workers should not have to go through a time-consuming election, the results of which the hotel is likely to appeal over a period of years, Ruby added.

“You can get a huge loan with the power of your signature. You can buy a car with the power of your signature,” she said. “Adult, smart people who say they want a union by signing a card have expressed a choice.”

Chapman would not address Ruby’s assertion that management had rebuffed the cards, saying, “We believe our employees have a right to vote.”

The union tried to drum up public pressure on the hotel to accept the cards by holding a noisy rally on Valentine’s Day in front of the hotel. The Berkeley City Council recently passed a resolution expressing support for the spa workers. Oakland City Councilwoman Jane Brunner, who represented the former masseuses who sued over age discrimination, is sponsoring a similar measure.

Ruby said that a victory by the Claremont’s spa workers could spur unionizing at other spas.

“It’s really like the beginning of a whole new movement of workers in an industry that traditionally have not organized and I think are now realizing they are workers just like everybody else,” she said.

Nancy Griffin, president of The Wellness Resource, a spa industry consultant, concurred. “They all talk. The food and beverage people (and the spa workers) are in kind of the same environment.” Unionizing at spas “is not typical,” she added, “but it’s probably going to become a trend.”