The union representing workers on strike against troubled aerospace firm Boeing (BA) on Thursday reminded its members that they need to stick together in order to get what they want.

Sixty-four percent of workers represented by International Association of Machinists and Aerospace Workers (IAM) local 751 on Wednesday voted against Boeing’s latest deal, which offered a 35% raise but failed to meet the workers’ broader demands. Two key sticking points have been the size of the raise — the IAM has been seeking a 40% wage increase — and the restoration of Boeing’s pension, which was cut as a benefit for new employees a decade ago.

Machinists have been divided over the contract, with some arguing that they should be “grateful” for the deal and “vote accordingly,” while others want to stick out for that pension benefit,” The Seattle Times reported.

Rachel Sarzynski, a team lead on Boeing’s 777, told the Times that “some people are desperate” and just want to get back to work and get paid again. Union members have received $250 per week from the strike fund after the walkouts entered its third week — a major pay cut for many employees. Sarzynski added that Boeing’s latest offer has “absolutely divided people.”

The IAM on Thursday evening seemed to acknowledged that divide, reminding its members that no one “deserves to be bullied or disrespected” because of how they voted on the deal. “Bullying” fellow members, the union added, is “unacceptable and vile.”

“Each one of us made a choice, using our voice, deciding what was right for our families. That power to choose, the right to choose, is at the core of everything we stand for,” the IAM said in a statement. “Respect. Fairness. A future that we decide, not one handed down to us from corporate boardrooms. “

As for the strike negotiations, the latest offer came partially after an intervention from Acting Secretary of Labor Julie Su, which pushed both sides to return to the bargaining table.

Boeing in a statement said it was “disappointed” by Wednesday’s results; its CEO had told investors this week the company is “feverishly” working toward a solution. The IAM has said it will work to return to the negotiating table.

The strike has added to Boeing’s litany of problems, which were renewed this year after a piece of fuselage fell off a plane in January. The Federal Aviation Administration (FAA) imposed a continuing production rate cap so Boeing could address quality-control issues, which meant that the company has been sending billions of dollars in cash out the door for a while without the lost income.

The strike paused work on many of the plane models making up Boeing’s order backlog. Now, it has plans to lay off 10% of its workforce and raise tens of billions of dollars in cash to fortify its coffers amid lost revenue, but securing that funding was in part tied to ending the strike.

The company’s much-needed investment-grade credit rating hangs on by a thread, and losing it would make the path to recovery steeper and more expensive should Boeing need to borrow more money along the way. Fitch Ratings said last week that Boeing’s cash-raising actions “support liquidity amidst continued operational challenges” — but only if Boeing can reach an agreement for its machinists to be back on the job by the end of the year.

—Melvin Backman contributed to this article

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