
Key players on the Hill in Syria debate —
The Obama administration has asked Congress to delay voting on authorizing military action in Syria, but the White House will still push the idea in case diplomacy fails. Senate leaders Harry Reid, D-Nevada, left, and Mitch McConnell, R-Kentucky, control the process and will determine the initial language and format for any vote in the chamber.

Key players on the Hill in Syria debate —
The top two Republicans in the House -- Speaker John Boehner, left, of Ohio and Majority Leader Eric Cantor of Virginia -- both support military action in Syria. They will be key in negotiating language and may influence votes in their skeptical caucus.

Key players on the Hill in Syria debate —
House Minority Leader Nancy Pelosi, D-California, opposed the Iraq War but has stood firmly behind the president on Syria. Pelosi, who is known for her ability to assess votes, has the tricky job of convincing uncomfortable Democrats to sign on to a Syria deal.

Key players on the Hill in Syria debate —
Rep. Kevin McCarthy, R-California, the House majority whip, is responsible for corralling votes. He is undecided on military action.

Key players on the Hill in Syria debate —
House Minority Whip Steny Hoyer of Maryland is responsible for rounding up for votes on the Democratic side.

Key players on the Hill in Syria debate —
Sens. John McCain R-Arizona, right, Lindsey Graham, R-South Carolina, far left, Saxby Chambliss, R-Georgia, second from left, and Kelly Ayotte, R-New Hampshire, third from left, are all known as ardently pro-military. They are half of an eight-member bipartisan group trying to negotiate a compromise resolution on Syria.

Key players on the Hill in Syria debate —
Sens. Chuck Schumer, left, of New York and Bob Casey of Pennsylvania are among the Democrats in the "Gang of Eight" working on a Syria compromise. Sens. Chris Coons of Delaware and Bob Menendez of New Jersey, who are not pictured, are the other two Democrats. Casey was an early hawk on Syria , while Schumer, who's known as a strong negotiator, was initially undecided before becoming a cautious yes on military action.

Key players on the Hill in Syria debate —
Sen. Chris Coons, D-Delaware, is a member of the "Gang of 8" looking for a compromise on Syria. Coons is backing military action in Syria despite pressure from antiwar constituents in his state.

Key players on the Hill in Syria debate —
Rep. Chris Van Hollen, D-Maryland, will be key to watch to see how language of a possible resolution shapes up in the House. He has drafted a potential compromise plan that gives Syria 30 days to agree to secure its chemical weapons.

Photos: Key players on the Hill in Syria debate —
Rep. Keith Ellison, D-Michigan, co-chairs the Congressional Progressive Caucus, made up of 72 Democrats, and is a member of the Congressional Black Caucus. Ellison, the first Muslim elected to Congress, is in favor of military action in Syria, though he is generally antiwar and "vastly prefers" diplomacy, a spokesman says. As the Democrats' chief deputy whip, he knows how to count votes.

Key players on the Hill in Syria debate —
Rep. Devin Nunes, right, is one of few House Republicans openly working on a possible compromise resolution on Syria. The Californian also sits on the House Intelligence Committee. Rep. Jim Costa, R-California, is at right with Jason Hubbard.

Key players on the Hill in Syria debate —
Rep. Jim Clyburn, D-South Carolina, right, is the third highest-ranking House Democrat, while Rep. Barbara Lee, D-California is a former chair of the Congressional Black Caucus. They could influence caucus members' important votes on Syria. Clyburn is undecided on military authorization, while Lee is a "no."