Senate Republicans were successful today in an attempt to block an amendment to the 2008 defense authorization bill that would have mandated that soldiers receive a certain amount of time off between deployments. Sen. Jim Webb, D-Va., who introduced the amendment -- the first to be considered as the Senate debates the bill -- withdrew it after a cloture vote, intended to limit debate on the measure and thus block a Republican filibuster, failed.

The cloture vote needed 60 votes to succeed, but it fell four short; the final tally was 56-41. Seven Republicans -- Sens. Chuck Hagel, R-Neb., Olympia J. Snowe, R-Maine, John W. Warner, R-Va., John E. Sununu, R-N.H., Norm Coleman, R-Minn., Gordon H. Smith, R-Ore., and Susan Collins, R-Maine -- joined Democrats, as did Vermont independent Sen. Bernie Sanders. The Senate's other independent, Connecticut's Joe Lieberman, voted against cloture.

On Tuesday, the Bush administration threatened a veto of the entire authorization bill if Webb's amendment -- or any amendment that set a timetable for the withdrawal of U.S. troops from Iraq or dictated the U.S. mission there -- was included, CQ reports.