Just two members of Massachusetts' all-Democratic congressional delegation have voted to give President Barack Obama the authority to train and arm Syrian rebels.

The measure passed on a 273-156 vote Wednesday. Obama called the training an important step toward confronting the Islamic State group.

Of Massachusetts' nine-member delegation, only congressmen Stephen Lynch and Richard Neal voted for the measure.

The rest of the delegation — Reps. Michael Capuano, Katherine Clark, William Keating, Joe Kennedy, James McGovern, John Tierney and Niki Tsongas — opposed the proposal.

Tsongas called the amendment "a back door vote" that could lead to an open-ended commitment. Kennedy agreed and said the vote shouldn't be taken "lightly, quickly, or piecemeal."

Even some members of Congress who voted for the measure said they were concerned about the possibility of escalation.