(CBS News) President Obama wants Congress to back a military strike on Syria, but with lawmakers not set to come back until next week, Mr. Obama is meeting Monday with one of his biggest critics -- Sen. John McCain, R-Ariz., to try and get some help making his case.
CBS News has heard from a number of members who say they're either on the fence or leaning towards voting against a strike. So the White House has a sales job to do over the next week-and-a-half or so, and it started on Sunday with a classified briefing that drew nearly a quarter of Congress back from their holidays to Washington.
The newly-empowered lawmakers streamed into the Capitol to get a closer look at top secret evidence the White House says proves that Bashar Assad used chemical weapons to kill his own people.
"It is not only a red line the president has drawn, but more or less our human society has drawn," said Sander Levin, D-Mich., "and there has to be a focused response."
Most members said they were glad the president decided over the weekend toto strike Syria. But that goodwill does not mean he has their votes.
"I'm a 'no' based on the information I have now," said Rep. Scott Rigell, R-Va.
"The mood from my district is 'do not do this,'" said Rep. Michael C. Burgess, R-Texas.
The battle lines were not strictly partisan. Rep. Eleanor Holmes Norton, a Democratic representative from Washington D.C., said the administration still had "a lot more explaining to do."
Rep. Jim Himes, D-Conn., seemed to agree with that assessment: "Today on this current resolution I would vote 'no'."
Some lawmakers on both sides of the aisle still regret their votes to go to war in Iraq 11 years ago. Others worry about the lack of international support.
"I feel terrible about the chemical weapons that have been used," said Rep. Janice Hahn, D-Calif. "However, we know that chemical weapons have been used in other instances, and we did not take military action."
Even the president's supporters argued the resolution proposed by the White House this weekend, granting President Obama authorization to use force "as he determines to be necessary and appropriate" is written too broadly and must be revised before a vote.
"I would support a very narrowly tailored, narrowly-crafted resolution, that made it clear that U.S. troops would not be on the ground," said Rep. Chris Van Hollen, D-Md.
McCain said he believes that in the end the resolution will pass because its failure would hurt the president's standing abroad.
"If Congress overrules a decision of the President of the United States on an issue of national security, that could set a catastrophic precedent in the future," said McCain.
But even he was not ready to say whether he would vote for the resolution. What he and so many others want is more information about the president's strategy and how far he's willing to go. And they are holding out on voicing their support until they can get it.
Watch Nancy Cordes' full report above.