WASHINGTON (AP) — President Barack Obama's trade bill faced a crucial test vote in the Senate, and Washington state Democratic Sen. Maria Cantwell saw an opportunity.

In a tense drama that unfolded in real time on the Senate floor Thursday, Cantwell withheld her vote to move forward on the trade legislation until she received assurances from Senate Majority Leader Mitch McConnell, R-Ky., that the Senate would vote on renewing the Export-Import Bank.

The Ex-Im Bank is a little-known government agency that guarantees loans to help U.S. exporters. One of its major beneficiaries: Boeing Co., which employs 80,000 people in Washington state.

But Cantwell said she thought not of Boeing but of a little company in Yakima., Wash., that exports music stands to China as she made her stand in the Senate well. She negotiated first in a group with Sens. Roy Blunt, R-Mo., Lindsey Graham, R-S.C., and others, gesturing and tapping her finger on a desk for emphasis.

Then she disappeared into the cloakroom, leaving senators milling in uncertainty on the Senate floor as the trade vote ticked forward. When she reappeared, she and Washington state's senior senator, Democrat Patty Murray, made their way to McConnell and stood in intense discussion before Cantwell signaled her "aye" vote on the trade bill. Murray quickly followed suit, as did Graham and Democratic Sens. Heidi Heitkamp of North Dakota, Chris Coons of Delaware and Claire McCaskill of Missouri.

A deal had been struck, and the trade bill advanced on a vote of 62-38, narrowly clearing the 60-vote threshold. The trade legislation is a top Obama priority as it would allow him to get trade deals through Congress without amendment and pave the way for a landmark pact with Asian nations.

Afterward, Cantwell said in an interview that she was determined to ensure a future for the Export-Import Bank in the face of threats from House conservatives who view it as corporate welfare and have vowed to kill it. McConnell promised her a vote in June, and she expressed confidence that the bank would be reauthorized before its expiration at the end of that month, despite GOP opposition.

"The fact that these guys wouldn't make a commitment to that was very frustrating, so we wanted to make the point that we weren't willing to continue the trade debate until they gave us that commitment," said Cantwell, 56, who made millions at a software firm before her election to the Senate in 2000 and is known for her intensity and persistence.

She called the Export-Import Bank "a vital tool for U.S. manufacturers when it comes to reaching new market opportunities around the globe."

Cantwell didn't get all that she wanted. She had sought a commitment from House Speaker John Boehner for a vote on long-term renewal of the bank before the end of June, which he denied he gave her. But Cantwell seemed satisfied with what Boehner did agree to: bringing up the legislation passed by the Senate, subject to amendment.

And Cantwell consulted repeatedly over the phone with Obama, she said, receiving assurances that "the president now is very committed to making this part of the entire trade package."

Her moves did not go unnoticed by Boeing, whose executive, James McNerney, was on the Hill Thursday morning to meet with Senate Democratic leaders. Company spokesman Tim Neale said, "She's been very supportive of us on this issue which we really appreciate."