WASHINGTON — A key Senate panel approved the nomination of Congressman Jim Bridenstine as NASA's next administrator but the party-line vote on President Trump's nominee portends potential trouble for the Oklahoma Republican when the full Senate takes up his confirmation later this year.

The vote was 14-13 in the Senate Commerce, Science and Transportation Committee with Republicans supporting Bridenstine and Democrats opposing him.

Florida Sen. Bill Nelson, the committee's senior Democrat and one of NASA's biggest champions in Congress, said NASA's important challenges ahead — including the planning of a Mars mission — required a non-partisan leader with deep executive experience and a scientific background who could unite people.

"I believe that the nominee falls short in these three areas," Nelson said before the vote.

NASA employs about 18,000 workers and has an annual budget of roughly $19 billion. It's primarily charged with conducting space exploration missions, developing supersonic aircraft, and launching satellites that measure changes in Earth's climate and ocean temperatures.

The vote comes a week after a contentious confirmation hearing in which Democrats assailed President Trump's nominee for his past skepticism of climate change, his condemnation of LGBTQ protections, and his criticism of fellow GOP lawmakers during the 2016 presidential campaign.

One of those lawmakers, Florida Republican Sen. Marco Rubio, has expressed misgivings about having an elected politician running the space agency. Bridenstine appeared in ads on behalf of Texas GOP Sen. Ted Cruz that suggested Rubio, then a candidate for the White House, was soft on terror because the Florida senator had supported immigration reform.

Bridenstine's nomination could be in trouble if Rubio and at least two of the other 51 Republicans in the chamber join Democrats in rejecting him.

At his confirmation hearing, Bridenstine sought to allay concerns that he would not respect the work done by NASA or bend to an ideological curve. He pledged to "build on the work" of the Obama administration and pursue "a consensus agenda driven by science and based on national interests."

He also touted partnerships with Democrats on space-related initiatives, especially on weather forecasting improvements and an expanded role for private companies operating in Earth's orbit.

"When it comes to space issues and when it comes to issues that are important to the national security of this country, I have worked across the aisle," he told the committee.

If the Senate confirms the 42-year-old former Navy flier, he would be the first elected politician to hold a job that’s generally been the purview of scientists, engineers and astronauts.

Bridenstine, who sits on the House Science, Space and Technology and the Armed Services committees, doesn’t have a formal science background. His last job before being elected to represent Oklahoma’s 1st District in 2012 was as executive director of the Tulsa Air and Space Museum & Planetarium.

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