WASHINGTON - Democrats steered the Senate into an attention-grabbing, all-night session to dramatize opposition to the Iraq war but conceded they were unlikely to gain the votes needed to advance troop withdrawal legislation blocked by Republicans. "Our enemies aren't threatened by talk-a-thons, and our troops deserve better than publicity stunts," said Sen. Mitch McConnell of Kentucky, the Republican leader. McConnell and many other Republicans favor waiting until September before considering any changes to the Bush administration's current policy. They have vowed to block a final vote on the Democrats' attempt to require a troop withdrawal to begin within 120 days....