The case of a clash between Uber, the city of Seattle, and labor unions has put a new spin on an old saying: If you can't beat 'em, make them join you.

The hired car company, which has capitalized on its popularity with voters to drive circles around the entrenched interests of the cab and livery lobbies, their unions, and the politicians who support them, has generally settled into a state of normalcy in most places it does business. Naturally, then, the time is ripe for a shakedown by unions. Seattle, home to the $15 minimum wage, is giving the Teamsters their first crack at Uber, the Seattle Times reports:

Mayor Ed Murray and the City Council are playing hot potato with a key part of Seattle's first-in-the-nation ordinance allowing taxi and Uber drivers to unionize. Each wants the other to decide which drivers will get to vote on unionization, a crowd of anxious drivers learnedWednesday during a tense council meeting. The council passed the ordinance in December giving independent-contractor drivers the right to opt for collective bargaining with companies such as Uber. But it left some decisions about the ordinance's rules up to the director of the Finance and Administrative Services (FAS) department, who works for the mayor. … Councilmember Mike O'Brien, who worked with Teamsters Local 117 on the ordinance, initially proposed giving votes only to drivers with at least 150 completed trips in the past 30 days. But he removed that condition before the council's vote, punting the decision to FAS.

Uber has contracted with a research firm to better understand the city's labor union-political dynamic. Meanwhile, the ordinance was challenged in court by the U.S. Chamber of Commerce, but a judge dismissed the lawsuit last week.

The ordinance might be law, and the lawsuit thrown out, but there's still a window for Uber to stop the unionization effort. Who gets to vote on unionization?

Uber, with its varied service options (Uber Black Car, UberXL, UberX, Uber Ride Share) has many classes of drivers from all walks of life. College students and teachers, for example, might drive more in the summer months than during the school year. Others might be recently unemployed and drive full time, or might be full-time livery drivers who use their Lincoln Towncar as a profit generator when not on duty.

Unlike most unionized professions, Uber is a flexible, money-generating job option that allows qualified drivers to work as little or as much as they'd like to. Uber argues that a collective bargaining agreement could take away that flexibility, saying in an FAQ to Seattle drivers:

The union would have the power to negotiate with Uber, Lyft, as well as the taxicab and for-hire companies over all terms and conditions of the drivers' work (including when they drive, where they drive, required background checks, and more).

The breakdown of who wants who to vote is, well, predictable. The Teamsters prefer that full-time drivers, who stand to benefit, should be the ones voting. Alas, more than 50 percent of Uber drivers drive fewer than 10 hours a week, meaning a vast majority of drivers don't meet the traditional definition of full-time drivers. Uber, of course, wants to give all drivers a vote. Union critics argue that's because part-time drivers are less likely to want to join their union.

Full-time or part-time, definitions haven't risen to the forefront of the debate because the city council and the mayor haven't been able to agree on who will determine who votes.

The unionization ordinance passed over the mayor's refusal to sign the council's unanimous vote. The Seattle Times reported the mayor "cited concerns about legal and administrative costs and said the council should not have left so much up to FAS [the Finance and Administrative Services department]." In other words, the city council tried to outsource the tough decision-making to bureaucrats.

Mayoral aide David Mendoza told the Times, "Because this was council-generated legislation, the executive does not wish to make a unilateral decision on this important question [of who gets to vote on unionization]."

The city council has given the mayor's FAS department an additional two months to research the decision, but all indications are that Seattle's mayor will try to force the city council to actually vote—on who should vote.

Suffering membership problems and facing pension financing woes, the Teamsters have found a potential financial savior: Uber drivers and their customers. If they're victorious in Seattle, expect other friendly legislators in other cities to join the cause.