March 25 (UPI) -- Republican senators have again backed President Donald Trump's war against Iran, blocking a Democratic-led effort to curb his ability to wage war without congressional approval.

The Senate voted 53-47, mostly along party lines, on Tuesday evening to block Democrats' war powers resolution, the third time Senate Republicans have blocked a resolution to require the removal of U.S. forces from hostilities against Iran unless Congress authorizes them.

Sen. Rand Paul of Kentucky was the only Republican to vote in favor of the motion with his Democratic colleagues, while Sen. John Fetterman of Pennsylvania was the only Democrat to vote against it with the GOP lawmakers.

Since the war began on Feb. 28, when the United States and Israel attacked Iran, Democratic lawmakers have argued the war is unconstitutional because only Congress has the power to declare war, while Republicans contend Trump is within his authority as commander in chief to defend the country.

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