The proposal to bomb Syria is dividing both political parties. But the dilemma is most acute for Senate Republican leaders worried about libertarian challengers to their re-election bids back home.
Unlike his House counterparts, Senate Republican leader Mitch McConnell took no clear stand on the matter Tuesday. He's letting rank-and-file colleagues debate whether to approve President Barack Obama's proposal to fire missiles at Syrian government targets.
McConnell faces a challenger from the right in Kentucky's GOP Senate primary next year. His fellow senator there is tea party hero Rand Paul. Paul leads noninterventionist lawmakers who say attacking Syria is not in the United States' interest.
McConnell's caution on Syria contrasts with the support Obama received Tuesday from the House's Republican leaders.
Congress' Democratic leaders also back Obama on Syria.