Russian President Vladimir Putin has gained momentum on his push for a diplomatic solution to the U.S. call for strikes on Syria.

WASHINGTON – As President Obama agreed Tuesday to explore Russia’s proposal for Syria to turn over its chemical weapons to international authorities, a bipartisan group of senators worked to draft a resolution to provide for a diplomatic solution while preserving the option for a military strike.

Obama met separately on Capitol Hill with Senate Democrats and Republicans to build support for a congressional resolution that would authorize the use of force against Syrian President Bashar Assad’s government. But he prospects for passing the resolution approved by the Senate Foreign Relations Committee last week appeared to be dimming, and Senate Majority Leader Harry Reid (D-Nev.) indefinitely postponed an initial vote on it.

Syria’s acceptance of Russia’s proposal to turn over control of its chemical weapons stockpiles only added to growing calls of lawmakers for a nonmilitary response. Now, key senators are in the early stages of drafting language that would incorporate the Russian offer, perhaps authorizing force only if Syria refused to allow an outside entity, most likely the United Nations, to secure its weapons stockpile. It could also require a U.N. resolution condemning Syria for using chemical weapons on its own people.

TRANSCRIPT: Obama's remarks on Syria

Sen. Carl Levin (D-Mich.), chairman of the Armed Services Committee, emphasized that the proposal was still being formed. But he said the goal was to eliminate the threat of Syria using chemical weapons by keeping open the possibility of force, “like the Sword of Damocles over Assad.”

“It’s because of the threat of strike by the president, because of the possibility that Congress would authorize it, that there’s movement at the U.N. So you’ve got to find a way to keep that pressure on. That’s the key to success at the U.N.,” Levin said.

Sen. Dianne Feinstein (D-Calif.), after speaking with another key partner in the effort, Sen. John McCain (R-Ariz.), said she thought it was “a good path forward,” and could take up to a week to be introduced.

Obama, along with his French and British counterparts, agreed Tuesday to work with Russia and China to explore the proposal to put Syrian chemical weapons under international control. Obama spoke with French President Francois Hollande and Prime Minister David Cameron separately Tuesday.

An advisor to Obama said the administration is interested in a diplomatic solution in which the Syrian government would turn over all its chemical weapons, and will begin work at the United Nations Tuesday to look at how to put together a U.N. Security Council resolution.

The president's visit with Democratic senators stretched into overtime as he fielded some two dozen questions, including a discussion of the nascent plan as well as another by Sen. Joe Manchin III (D-W.Va.) that would give Syria 45 days to come into compliance with the Chemical Weapons Convention before authorizing force.

The president indicated he needed a number of days to pursue the diplomatic channel. But he “was not overly optimistic,” said Sen. Richard Durbin (D-Ill.), the assistant majority leader.

FULL COVERAGE: The debate on Syria

“What he’s basically asked is for some time to work this out,” Durbin said, a time frame he said would last into next week. “I think that’s reasonable. We want this to end well, we want the end of chemical weapons in Syria. And if we can achieve that through the president’s threatened use of military force, that’s a good thing for safety in the world.”

Reid told reporters that he would be satisfied with a diplomatic solution. “I’m not a blood-and-thunder guy. I’m not for shock and awe,” he said. But he added that it was essential that “the credible threat of our doing something about this attack is going to remain.”

Manchin said he handed Obama a draft of his proposal and that the president was “receptive” to his ideas. “The president wants to make sure that they understand that he means business. I understand where he’s coming from. I just respectfully disagree on the military strike,” he said. “He wants to keep his finger on the pulse if you will, and on the trigger if needed.”

Obama also met with Republican senators, calling it a “good conversation.”

Sen. Mark Steven Kirk (R-Ill.) said the president asked them not to undercut his efforts to deter Syria from using chemical weapons again. Kirk also said Obama acknowledged he cannot change public opinion, which is running strongly against U.S. military action against Syria.

"I don’t think we need to rush out with our hair on fire right now," said Sen. Bob Corker (R-Tenn.), as he emerged from Obama’s meeting with Republican senators. "Our best course of action is to pause, to understand whether this is credible or not."

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