Striking Boeing workers set to vote on new contract offer. Will they approve it?

Tens of thousands of striking Boeing machinists are set to vote this week on a new contract proposal that could end the weekslong work stoppage at the embattled aerospace company.

Workers overwhelmingly rejected a previous offer last month, leaving the outcome of the impending vote uncertain.

The new offer delivers a 35% raise over the four-year duration of the contract, upping the 25% cumulative raise provided in the previous offer, said the International Association of Machinists and Aerospace Workers (IAM), the union representing 33,000 Boeing workers. The offer, however, falls short of workers' demand for a 40% cumulative pay increase.

The proposal also hikes Boeing's contribution to a 401(k) plan, but it declines to fulfill workers' call for a reinstatement of the company's defined pension.

Experts who spoke to ABC News said the new contract has a good chance of gaining majority support from the union members, citing an improved offer as well as the financial pain felt by workers and company alike amid the dispute.

They cautioned though that it is difficult to predict how workers will respond in the midst of a spirited, high-stakes standoff.

"This is a much better offer than we have seen from Boeing," Henry Harteveldt, a travel industry analyst at Atmosphere Research Group, told ABC News. "It doesn't get the workers everything they want but it gets them closer."

In response to ABC News' request for comment, a Boeing representative pointed to a statement posted on the company's website on Saturday, saying, "We look forward to our employees voting on the negotiated proposal."

IAM did not immediately respond to ABC News' request for comment. In a statement posted online, the union said: "With the help of Acting U.S. Secretary of Labor Julie Su, we have received a negotiated proposal and resolution to end the strike, and it warrants presenting to the members and is worthy of your consideration."

The company and its workers have suffered financial losses from the five-week strike.

Union members have received $250 per week from a strike fund, beginning in the third week of the work stoppage. That compensation marks a major pay cut for many of the employees.

Mid-ranking workers involved in the strike typically make $20 per hour, which totals $800 per 40-hour work week, while higher-paid members earn salaries upward of $100,000 per year, or nearly $2,000 per week

"Being out on strike can change your perspective," Art Wheaton, director of labor studies at the Worker Institute at Cornell University, told ABC News. "Contract proposals can start to look good compared to being out on the picket line for another month or two in the cold."

Meanwhile, the strike was set to cost Boeing $108 million per day in lost revenue, amounting to as much as $5.5 billion in losses should the work stoppage last 50 days, investment bank TD Cowen said in a report reviewed by ABC News at the outset of the dispute. So far, the strike has lasted 38 days.

In September, Boeing announced furloughs and pay cuts for some white-collar employees in response to the strike. Last week, Boeing CEO Kelly Ortberg announced plans to cut 17,000 jobs, which amounts to about 10% of its global workforce.

"That's a wake-up call for the rank and file," Jake Rosenfeld, a professor of sociology at Washington University in St. Louis, who studies labor, told ABC News. "The firm they're striking against is making clear that it's not in good shape."

Still, some workers may consider the company's recent concessions, as well as its financial pain, as evidence of union leverage that could allow for a better deal if the strike continues, Richard Aboulafia, managing director of aerospace consulting firm AeroDynamic Advisory, told ABC News.

"They have more power than they've had in decades to get things that might or might not be realistic, and that's the biggest risk," Aboulafia said. "They do have a lot of leverage."

The most recent IAM strike against Boeing in the Pacific Northwest, in 2008, lasted 57 days. Work stoppages undertaken by unionized Boeing employees in the same region have historically lasted an average of 60 days, a Bank of America Global Research analysis found after examining seven previous strikes, the earliest in 1948.

Workers will cast their ballots in a ratification vote on Wednesday. If a majority of workers back the proposal, the contract will be adopted and the strike will end.

Shares of Boeing climbed as much as 5% in early trading on Monday, suggesting that many traders expect workers to ratify the deal.

"That doesn't make it the correct view," Aboulafia said, noting that it is difficult to assess the sentiment of striking workers.

"They're getting a lot of what they want," he added. "The question is how many of them are happy with that."