Supporters of oil pipeline scramble for last vote

Members walk down the steps of the House side of the U.S. Capitol after voting on the Keystone XL pipeline, Nov. 14, 2014, in Washington.
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With the clock ticking, supporters of a Senate bill to approve the Keystone XL pipeline from Canada to the Texas Gulf Coast are still scrambling to find the last vote.

With 59 Senators publicly voicing support, the hunt's on for the 60th vote to advance the measure before a critical vote Tuesday.

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The issue has taken center stage in the waning days of this Congress in hopes it will boost the prospects of Louisiana's Senate candidates.

Democratic Sen. Mary Landrieu pushed for the Senate vote. Her rival, Republican Rep. Bill Cassidy, sponsored the bill the House passed late last week.

All 45 Senate Republicans support it, along with 14 Democrats.

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The White House has issued veto threats of similar bills.