A majority of nurses at St. Vincent Hospital in Worcester voted to keep their union, ending months of speculation about the union’s future at the medical center.

After a historic 301 days on strike before settling on a new contract, the nurses spent much of February voting to either keep the Massachusetts Nurses Association as their union or oust it from the hospital. The vote to decertify the union emerged from some nurses’ opposition to the union and its strike. If nurses had voted to oust the union, the new labor agreement with the hospital would have been null and void.

But results released by the National Labor Relations Board Monday evening showed nurses voted 302 to 133 in favor of keeping MNA.

“We’re really exuberant on this win,” Dominique Muldoon, a St. Vincent nurse and co-chair of the union’s bargaining committee, told GBH News. “This is good for nurses and patients. ... We feel so happy we can close the chapter on this whole thing.”

The nurses’ strike ended in January after 10 months with a new contract that includes higher wages and improved nurse-to-patient staffing ratios. But nurses opposed to the union — including C. Richard Avola — argued it was inappropriate to lead a strike for that long during a pandemic.

Avola formally triggered the vote when he filed a petition with the National Labor Relations Board to decertify the union.

“It was difficult fighting the MNA,” Avola said Monday night. “I am proud of what I have done, and I have started a wave of change.”

St. Vincent’s CEO Carolyn Jackson urged nurses to oust the union. But in a statement after the vote, a spokesperson for the hospital said it “respects the decision of its nurses to continue to be represented by the MNA.”

“We continue to foster a culture and team that is committed to providing quality care to the Greater Worcester community,” the spokesperson said.

Nurses who supported the union said relations with their co-workers who oppose the union remain tense. Muldoon called on all nurses to unify.

“I don’t think any of us wants any divisiveness,” Muldoon said. “We want to come in and do our jobs.”