Washington (CNN) -- In a graphic example of election-year politics at work, a defense bill that would repeal the military's "don't ask, don't tell" policy got blocked Tuesday in the U.S. Senate by a Republican-led filibuster. The bill stalled on a 56-43 vote, four short of the 60 votes needed to overcome the Republican opposition. Senate Majority Leader Harry Reid, D-Nevada, changed his vote to "no" as a tactical move, allowing him to bring the measure up later. Reid and other Democrats accused Republicans of stalling the National Defense Authorization Act, which traditionally passes with bipartisan support, to undermine the "don't ask, don't tell" repeal and an immigration provision offering a path to citizenship for students and soldiers who are children of illegal immigrants.
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NEW: McCain accuses Democrats of cynical stance on defense bill
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NEW: Durbin says Republicans wanted to kill immigration provision
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Defense bill that would repeal the "don't ask, don't tell" military policy is blocked
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White House disappointed but says "we'll keep trying"
Reid had said he wanted the @placeholder to take up the bill now, but no final vote would take place until after the November 2 elections.