In what could be a precedent-setting victory for the modestly paid service-industry workers who help keep the Silicon Valley economy humming, shuttle bus drivers who take Facebook employees to and from work will vote Wednesday on whether to unionize, hoping success at the poll will lead to others joining what they say is a campaign for better pay and working conditions.

With the region’s economy on fire, many of the nearly 400,000 members of the new tech elite pull down six-figure salaries, even as they depend on a shadow workforce with services provided by an army of lower-paid drivers, cafeteria workers and janitors. A yes vote by a majority of the 84 full- and part-time drivers for Facebook’s shuttle bus contractor, Loop Transportation, could kindle a new labor-force paradigm in Silicon Valley, experts say, prompting other drivers to unite in their fight for better pay and work schedules in one of the country’s most expensive places to live.

“A lot of my passengers are young enough to be my kids and are making a lot more than I do,” said Cliff Doi, a 55-year-old Loop driver who said he’ll vote to join the Teamsters at Wednesday’s election. “I’m not saying I should be paid what they are, but a little bit higher wage that’s more appropriate for this market where the cost of living is so high would help a lot.”

Results of the election, which will take place at two of Loop’s properties on the Peninsula and be monitored by a representative of the National Labor Relations Board, could be known shortly after 5 p.m. Either party may file objections to the vote’s outcome with the NLRB within seven days. After that is resolved, if the drivers get enough yes votes, the Teamsters would be certified as the employees’ bargaining representatives when they meet with Loop to negotiate a contract.

Facebook declined to comment on the vote, even as drivers and their supporters rallied Tuesday in front of the company’s Menlo Park headquarters. Their previous attempt to personally lobby Facebook CEO Mark Zuckerberg to intervene on their behalf was unsuccessful. But Loop President Jeff Leonoudakis said he thought the drivers’ actions were misguided.

“We’re not in favor of the union because we don’t think it’s necessary,” said Leonoudakis, who has publicly defended what he called Loop’s generous medical and dental insurance plans and overtime policy. “We’re pretty proud of the wages-and-benefits package and working-schedule conditions we’ve structured.”

But it’s precisely those scheduling issues that helped galvanize disgruntled employees earlier this year. Their big complaint centered on split shifts, forcing drivers living far from the pricey Peninsula to have to sleep in their cars midday between shuttling Facebook employees to work in the morning and taking them home again at night. Further fueling the drivers’ discontent is knowing that the people they see face to face every day on their buses are so highly compensated, with the average Facebook software engineer bringing home close to $120,000 a year, according to Glassdoor.

Jimmy Maerina said he and his fellow drivers make $18 an hour, which he says is less than drivers for other tech companies get and should be more. By comparison, drivers for SF Muni, AC Transit and SamTrans can make as much as $25 or even $30 an hour.

“It’s hard to live in the Bay Area on our wages,” Maerina said. “Eighteen dollars is just not enough, especially since Facebook’s such a big successful company. We should be getting more money for driving their employees back and forth to work.”

Maerina and others say a successful vote to unionize could take on even greater significance if it ends up inspiring others to follow suit. Indeed, Maerina and Teamster organizers say drivers for Google and Apple have contacted them about launching their own union drives. San Jose State sociology professor Scott Myers-Lipton thinks the Facebook drivers’ actions could signal to other lower-wage workers that union representation may be a way to narrow the income gap in the Valley.

“I think we’ll see more and more working people like these shuttle drivers pushing for better wages and working conditions,” Myers-Lipton said. “Wages have remained stagnant while these top tech icons are booming and showing record profits. Average Americans are saying that they just want to share in the growth that’s going on around them, especially here in Silicon Valley.”

Contact Patrick May at 408-920-5689; follow him at Twitter.com/patmaymerc.