WASHINGTON - Mitt Romney is vowing to approve TransCanada's Keystone XL pipeline on his first day on the job if elected U.S. president in November.

In a campaign ad unveiled on Friday, the presumptive Republican nominee asks voters to imagine Day 1 of his presidency, and lists Keystone as a top priority.

"Day One, President Romney immediately approves the Keystone pipeline, creating thousands of jobs that Obama blocked," the ad's narrator says.

Romney has been maligning U.S. President Barack Obama for months for failing to give the green light to Keystone. The president rejected the $7 billion pipeline earlier this year, but invited TransCanada to apply for another permit once the Calgary-based company rerouted the project around a crucial aquifer in Nebraska.

"I will build that pipeline if I have to myself," Romney said last month.

TransCanada recently came up with a new route for Keystone XL, one that skirts the Nebraska aquifer before joining up with the original proposed path of the pipeline.

Environmentalists say the new route continues to pose threats to Nebraska's drinking water since it still traverses the aquifer, only avoiding a portion of the state's Sandhills region where groundwater is close to the surface.

U.S. environmentalists have mounted a massive campaign against the pipeline, calling it a disaster waiting to happen and insisting it would sustain America's addiction to "dirty oil."

Keystone XL would transport oilsands crude from northern Alberta through six U.S. states to Gulf Coast refineries.

The debate over the pipeline became a political migraine for Obama. Keystone XL proponents said he was turning his back on much-needed American jobs by stalling on the Canadian pipeline, while environmentalists urged him to stand up to the oil industry as he promised to do while running for president in 2008.

The State Department will make the final decision on the pipeline because it crosses an international border.

Earlier on HuffPost:

CELEBRITIES AGAINST THE KEYSTONE PIPELINE
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  • Dalai Lama

    In September 2011, the Dalai Lama was one of nine Nobel Peace Prize laureates who <a href="http://www.huffingtonpost.ca/2011/09/07/nobel-peace-prize-winners_n_952248.html" target="_hplink">sent a letter to U.S. President Barack Obama</a> urging him "to say 'no' to the plan proposed by the Canadian-based company TransCanada to build the Keystone XL, and to turn [his] attention back to supporting renewable sources of energy and clean transportation solutions."

  • Archbishop Desmond Tutu

    Archbishop Desmond Tutu was among<a href="http://www.huffingtonpost.ca/2011/09/28/nobel-prize-winners-oil-sands_n_985171.html" target="_hplink"> a group of Nobel Peace Prize laureates</a> who signed letters to both U.S. President Barack Obama and Canadian Prime Minister Stephen Harper, urging the men to stop the Keystone pipeline.

  • Al Gore

    Gore has said it is essential to stop the Keystone pipeline because the tar sands oil it would carry is "the <a href="http://www.huffingtonpost.com/al-gore/the-dirtiest-fuel-on-the-_b_944186.html" target="_hplink">dirtiest source of fuel on the planet</a>."

  • Robert Redford

    Actor and environmentalist <a href="http://www.imdb.com/name/nm0000602/" target="_hplink">Robert Redford</a> recently added his name to the list of prominent individuals who are calling on President Obama to reject the Keystone XL pipeline. <a href="http://www.huffingtonpost.com/2011/10/24/robert-redford-keystone-xl_n_1019789.html" target="_hplink">In a video for <em>The New York Times</em>, produced with the Natural Resources Defense Council</a>, Redford described the negative aspects of the proposed tar sands pipeline and said, "By deepening our reliance on oil, the pipeline would be a job killer." Redford has previously been vocal about calling for alternatives to oil. <a href="http://www.huffingtonpost.com/robert-redford/keystone-xl-pipeline_b_978835.html" target="_hplink">Writing last month for HuffPost</a>, he said, "Let's build the next generation of energy efficient cars, homes and workplaces. Let's develop wind, solar and other cleaner, safer, more sustainable sources of power and fuel. Let's invest in high-speed rail and smart communities that give us better transportation options."

  • Mark Ruffalo

    Actor <a href="http://www.imdb.com/name/nm0749263/" target="_hplink">Mark Ruffalo</a>, famous for films like "<a href="http://www.imdb.com/title/tt0842926/" target="_hplink">The Kids Are All Right</a>" and "<a href="http://www.imdb.com/title/tt0443706/" target="_hplink">Zodiac</a>," is also an outspoken activist and opponent of the Keystone XL pipeline. Ruffalo <a href="http://www.huffingtonpost.com/2011/08/11/mark-ruffalo-tar-sands_n_924245.html" target="_hplink">said in a video</a> for the <a href="http://www.tarsandsaction.org/" target="_hplink">Tar Sands Action</a> group, "I've seen the kind of damage that out-of-control energy development can do to water and to communities near my own home, where fracking for natural gas is causing widespread pollution ... All these problems are connected -- we need to get off fossil fuels." In the past, Ruffalo has also expressed his ire for hydraulic fracturing natural gas extraction, or fracking. He told The Huffington Post, "The <a href="http://www.huffingtonpost.com/2011/01/18/mark-ruffalo-fights-frack_n_810461.html" target="_hplink">world is already leaving us behind</a>. We're being left behind. America. Because the gas and oil industry has a strangle hold on us. And our politicians."

  • Bill McKibben

    Environmentalist and author <a href="http://www.huffingtonpost.com/bill-mckibben/" target="_hplink">Bill McKibben</a> has expressed strong disapproval for the planned Keystone XL pipeline. In fact, he was <a href="http://www.tarsandsaction.org/press/releases/aug20/" target="_hplink">one of the first</a> of over 1,200 who were arrested at the Tar Sands Action sit-in at the White House in August. Referring to <a href="http://www.huffingtonpost.com/2011/08/23/keystone-xl-frustrated-environmental-activists-obama_n_933648.html" target="_hplink">his opposition to the Keystone Pipeline</a>, McKibben told HuffPost, "The people who've carried this fight for three years are indigenous people on both sides of the border who have a huge stake in it because it's on their land, and farmers and ranchers from places like Nebraska," he said. He added, "It wasn't until I sat down and read <a href="http://www.huffingtonpost.com/dr-james-hansen" target="_hplink">Jim Hansen</a>'s analysis of how much carbon was in those things that I understood that this was not just a national issue, it's a global issue of the first order."

  • Julia Louis-Dreyfus

    <a href="http://www.imdb.com/name/nm0000506/" target="_hplink">Julia Louis-Dreyfus</a>, known for her role as Elaine on the popular sitcom "Seinfeld," has released a video urging President Obama to reject the permit for the Keystone XL pipeline. Dreyfus recalls when Obama said "Let us be the generation that ends the tyranny of oil." But she says, "Big Oil is still pretty much running the show." She claims that by rejecting the pipeline, Obama has a chance to "make good on [his] word." <a href="http://www.tarsandsaction.org/video-release-julia-louis-dreyfus-challenges-pres-obama-stop-keystone-xl/" target="_hplink">Louis-Dreyfus asks Obama</a>, "Denying the permit for a brutally stupid, money-grab like the Keystone XL pipeline is a no-brainer, right Mr President?"

  • Nebraska Governor Dave Heineman

    Dave Heineman, the Republican governor of Nebraska, has officially stated that he opposes the Keystone XL project. As the governor of an agrarian state through which the pipeline would pass, Heineman expressed his concern for the pipeline's threat to Nebraska's vital water resources. According to the Associated Press, "Heineman said <a href="http://www.huffingtonpost.com/2011/08/31/nebraska-governor-opposes-pipeline_n_943610.html" target="_hplink">he supports pipeline projects</a> but opposes the proposed TransCanada Keystone XL route." In August, Heineman <a href="http://www.governor.nebraska.gov/news/2011/08/31_pipeline.html" target="_hplink">sent an open letter</a> to President Obama and Secretary of State Hilary Clinton urging them to "not allow TransCanada to build a pipeline over the Ogallala Aquifer and risk the potential damage to Nebraska's water."

  • Daryl Hannah

    Actress <a href="http://www.imdb.com/name/nm0000435/" target="_hplink">Daryl Hannah</a> has also lent her voice to the movement against the <a href="http://www.huffingtonpost.com/news/keystone-pipeline" target="_hplink">Keystone XL pipeline</a>. In August, Hannah was one of the over 1,200 people to be <a href="http://www.huffingtonpost.com/2011/08/30/daryl-hannah-arrested-keystone-protest_n_942072.html" target="_hplink">arrested as an act of civil disobedience</a> in front of the White House. Shouting "no to the Keystone pipeline" as she was handcuffed, Hannah made it clear she opposed the proposed Canada to Texas pipeline.

  • Maude Barlow

    Maude Barlow, a Canadian author and activist and chairperson of <a href="http://www.canadians.org/" target="_hplink">The Council of Canadians</a>, was arrested in September at a Keystone pipeline and oil sands protest on Parliament Hill in Ottawa. <a href="http://www.huffingtonpost.ca/2011/09/26/ottawa-oil-sands-pipeline-protest_n_981052.html" target="_hplink">She was one of over 100 protesters</a> of the demonstration's estimated 400 to be arrested. Writing for HuffPost Canada about <a href="http://www.huffingtonpost.ca/maude-barlow/maude-barlow-arrested_b_982487.html" target="_hplink">her first experience being arrested</a>, Barlow blogged, "I did it because I fear we are killing the planet and I can no longer be content to only write and speak about it. Today my feet spoke for me as I crossed that barricade and took away one more fear in my life." She also said, "By investing trillions of dollars into these pipelines, governments and the energy industry are ensuring the continued rapid acceleration of tar sands development, instead of supporting a process to move to an alternative and sustainable energy system."

  • Kyra Sedgwick

    <a href="http://www.imdb.com/name/nm0001718/" target="_hplink">Kyra Sedgwick</a>, star of the television crime drama "The Closer," has voiced her opposition to the pipeline. In a video for the <a href="http://www.nrdc.org/" target="_hplink">Natural Resources Defense Council</a>, Sedgwick said "Just like the BP oil spill, one glitch in the tar sands pipeline could destroy our clean water sources, possibly forever."

  • David Strathairn

    Joining several other prominent actors, David Strathairn appeared in a video urging President Obama to reject the Keystone Pipeline. He calls on his fellow Americans to join the November 6 <a href="http://www.tarsandsaction.org/" target="_hplink">Tar Sands Action</a> in Washington, D.C. <a href="http://www.imdb.com/name/nm0000657/" target="_hplink">Strathairn</a>, who is known for his portrayal of journalist Edward R. Murrow in "Good Night, and Good Luck," said, "Obama ran for office speaking of the dangers of our fossil fuel addiction, promising to fight climate change and fully embrace a clean energy future. The <a href="http://www.huffingtonpost.com/news/keystone-pipeline" target="_hplink">Keystone XL tar sands pipeline</a> is a dangerous step away from that commitment."

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