Whether deft diplomacy or a rhetorical stumble, US Secretary of State John Kerry has managed to crack open the door to a possible solution to the Syrian crisis that could get President Barack Obama and US lawmakers out of a bind, save Syria from a bombing and cast Russia as peacemaker.

Kerry's seemingly off-hand suggestion on Monday that Syrian President Bashar al-Assad might avert a US military strike if he surrendered all of his chemical weapons offered a potential escape hatch that no one had seriously proposed before - and that could end up leading nowhere.

But in a sign of how desperate the US, Russia, Syria and the United Nations are to defuse the international standoff over Assad's alleged use of chemical weapons in Syria's civil war last month, momentum for Kerry's suggestion seemed to build instantly.

Russian Foreign Minister Sergei Lavrov seized upon the idea, issuing a proposal for putting Syria's chemical stockpile under international control.

Positive to lukewarm reaction flowed in from the White House, Assad's government and the United Nations. On Capitol Hill, lawmakers in both parties expressed hope that a diplomatic solution would help them avoid a vote to either attack Syria - a plan most Americans oppose - or go against Obama's plea for authorization to attack.

By late afternoon, former Secretary of State Hillary Clinton - a potential Democratic presidential candidate in 2016 - was speaking out on the Syrian conflict for the first time, saying that a plan to rid Assad of his stock of chemical weapons had potential.

Even as Obama used a half-dozen interviews with television networks to continue pressing his case for military action in Syria and made plans for a nationally broadcast speech to Americans on Tuesday night, the sudden prospect of a deal with Russia dominated the conversation in Washington.

During an interview with NBC, Obama signaled that he might have to adjust his approach because of the Russian proposal.

He told NBC that the proposal was "potentially positive," but said that "we have to be skeptical," a reflection of the many questions surrounding the plan.

Obama and several lawmakers said it was important for Congress to move forward with its debate over authorizing US military force in Syria.

By all appearances, Obama has been losing that debate.

Vote count estimates by The Washington Post and The New York Times, among others, indicate that far more members of Congress oppose military action in Syria than support it - a reflection of Americans' wariness of engagement in another conflict in the Middle East.

The ongoing debate over military force could give the United States some leverage in any discussions of a deal with Russia, according to Obama and key lawmakers such as Arizona Senator John McCain.

However, Middle East analysts said that the idea of sequestering Assad's chemical weapons almost certainly would complicate Obama's efforts to win Congress' approval for military force.

"It basically throws a bit of a wrench into the administration's approach, but it may be a welcome wrench," said Robert Danin, a Middle East specialist and senior fellow at the Council on Foreign Relations.

Monday's drama began when Kerry, after a meeting with British Foreign Secretary William Hague, was asked by a reporter how military strikes on Syria might be averted.

Kerry said that Assad "could turn over every single bit of his chemical weapons to the international community in the next week. But he isn't about to do it, and it can't be done."

Perhaps not. But by merely floating the idea in what the State Department said was just an attempt to make a rhetorical point, America's top diplomat suddenly gave it credence.

After Lavrov responded with his proposal, Kerry called him and said that US officials were "not going to play games," but that if the Russian proposal was serious, "we will take a look," a senior State Department official said.

White House officials also expressed doubts about Assad's credibility in such a deal, but acknowledged that the idea was in play.

Clinton - who had met with Obama earlier in the day - then used a speech on wildlife preservation to suggest that the United States was interested in a solution that would rid Syria of chemical weapons.

To some analysts, it all sounded far-fetched.

A senior European security official deemed it a "fantasy" and said it would be "impossible to verify" whether Syria would give up its chemical weapons.

A former senior US intelligence expert said there was no full accounting of Assad's stockpile and where it is stored.

For Obama, however, a deal brokered by Russia could mean at least a temporary way out of a crisis that he helped to create.

Last year, Obama declared that Assad would cross a "red line" for US action if the Syrian president used chemical weapons in a civil war that now has gone on for 2 1/2 years and killed an estimated 100,000 people.

For Assad, such a deal could be a chance to delay or prevent a US-led missile strike that could weaken Assad's loyalists in their fight against rebel forces. Assad would, however, be under extreme pressure to make good on any pledge to identify and relinquish his chemical weapons.

And even though its Syrian ally is accused of using chemical weapons, Russia would have a chance to be seen as a peace-enabler while continuing to shield Syria from US retribution for last month's gas attack.

If Russia's proposal leads to a deal, Kerry's utterance that inspired the proposal could become a historic moment in US diplomacy - and an ironic symbol of how his spontaneous comments sometimes have complicated the Obama administration's efforts to sell the notion that military action in Syria is necessary.

Kerry, a former senator who joined the administration in February and became its most forceful voice for tougher action against Assad, faced criticism last week for initially refusing to rule out American "boots on the ground" in Syria before backtracking and accepting that restriction.

A senior US official said that Kerry's remarks on Monday about Assad giving up chemical weapons were not part of some carefully crafted diplomatic strategy aimed at finding a way out of the Syria impasse.

Kerry, the official said, was simply emphasizing what he saw as the unlikely possibility that Assad would give up such weapons.

"Then," the official said, "it kind of took off."-Reuters