Washington Senator Patty Murray, the fourth-ranking Senate Democrat, has officially endorsed President Barack Obama’s nuclear agreement with Iran, Politico reported Tuesday.

Though Murray had long been expected to line up behind the agreement, her formal announcement brings the Obama administration closer to the 34 votes needed in the Senate to sustain any veto of the resolution of disapproval on the nuclear deal, according to the website.

Murray is the 29th Senate Democrat to come out in favor of the agreement. Just two Senate Democrats have said they will oppose the deal in Congress: Senator Chuck Schumer of New York, the No. 3 Democrat, and Senator Robert Menendez of New Jersey.

In a statement Tuesday, Murray said she would prefer several elements of the nuclear deal to be “stronger” but warned that if lawmakers reject the agreement, it would only push Iran closer to developing nuclear weapons.

“[A]fter working my way through the details and the alternatives, losing a lot of sleep, and having a lot of good conversations with so many people, I am convinced that moving forward with this deal is the best chance we have at a strong diplomatic solution,” Murray said, according to Politico.

“It puts us in a stronger position no matter what Iran chooses to do, and it keeps all of our options on the table if Iran doesn’t hold up their end of the bargain,” she continued.

Still, Murray cautioned that she would be monitoring the Iran developments “closely” and that she will be “ready to join others in moving quickly on other options if Iran chooses to pursue an unacceptable path.”

Earlier this week, the Iran deal also received the backing of Senate Minority Leader Harry Reid, who said the deal, which lifts economic sanctions against the rogue nation for pledges to limit its nuclear program, is the “best way” to curtail Iran’s military ambitions.

Reid had previously been holding off on announcing his stance on the deal and had indicated he intends to talk with influential Jewish backers before deciding.

The Republican-led Congress must vote on a resolution of disapproval on the Iran nuclear deal by September 17. The deal’s backers have been working to deny GOP lawmakers and other opponents of the agreement the two-thirds majority needed to override any veto of the disapproval measure by Obama.