Opponents of a proposed $7 billion Canada-to-Texas oil pipeline say emails between an oil company lobbyist and the Obama administration reveal a pattern of “deeply disturbing” bias and corruption that undermines an impartial government assessment of the deal.

Friends of the Earth, an environmental group that obtained the emails through a Freedom of Information Act request, has been publishing the documents online in an effort to ratchet up pressure on the State Department, which is considering approval of the so-called Keystone XL project by the end of the year.

The emails show frequent, friendly and collaborative interactions between Paul Elliott, a lobbyist for TransCanada, the pipeline’s owner, and State Department staffers in Washington and Ottawa. Elliott is a former campaign aide to Secretary of State Hillary Clinton.

Activists say the “most disturbing document” is an exchange between Elliott and Maria Verloop, a State Department energy and environmental issues counselor, in which Verloop cheers Elliott’s success in winning support from Sen. Max Baucus, D-Mont., for the pipeline.

“Go Paul! Baucus support holds clout,” she wrote in a Sept. 10, 2010, email.

Elliott responded to Verloop later that day, saying lobbying “is a grind but when the grind pays off with support it makes it worthwhile.”

In a December 2010 email, Verloop told Elliott that “it’s precisely because you have connections that you’re sought after and hired.”

Critics say the exchanges and dozens more like them depict inappropriately “cozy” relations between Elliott and the Department, even if there is no sign of illegality.

Read more of the emails HERE.

“If President Obama remains true to his campaign promise that his election would mean an end to the days of lobbyists setting the agenda in Washington, he has no choice but to rescind the executive order delegating to the State Department the authority to sign a presidential permit for this pipeline,” Friends of the Earth said in a statement on its website.

“If the pipeline decision is made in the White House, rather than at the biased State Department, and if President Obama undertakes a fair and impartial analysis of the evidence, we believe he will reject this pipeline,” the group said.

Neither Clinton nor Obama have signaled their views on the pipeline, and administration officials insist the independent vetting process remains underway. Clinton is the final arbiter of the deal, which she is expected to rule on by the end of the year.

“We do not believe that there is any issue here with regard to affecting in an inappropriate manner the decisions that the secretary needs to make,” State Department spokeswoman Victoria Nuland said of the emails surfaced by Friends of the Earth.

Nuland said the documents depict only one side of multi-lateral consultations surrounding the pipeline. She also said no contact has occurred between Elliott and any administration staffers with direct influence on the final approval process.

The State Department concluded in August that the pipeline would have “no significant impact” on the environment, but the agency is still soliciting input on the matter.

There has been no apparent opposition to the plan from the Environmental Protection Agency or the Pipeline and Hazardous Materials Safety Administration, which have also been reviewing the plan.  Five of the six states through which the pipeline will pass have signed off, with  Nebraska the only one to raise concerns.

TransCanada, which says the project would create 20,000 jobs and provide U.S. access to Canadian oil, has beefed up lobbying in Washington to get the deal done.

Records show the company has spent $790,000 through the first half of 2011, surpassing all of what was spent last year, and nearly five times as much spent three years ago, according to the Center for Responsive Politics.

Activists say the high-profile role lobbyists have played make the pipeline case a test for President Obama, who pledged during the 2008 campaign to resist moneyed interests and “challenge the tyranny of oil.”

“On Nov. 6, exactly one year before the next election, we plan to encircle the White House with protesters, something I’m not sure has ever been done,” environmental activist and author Bill McKibben said last week in Rolling Stone.

McKibben was one of more than 1,200 demonstrators arrested at a White House protest in August. “We won’t be getting arrested; instead, it will be like a human Rorschach blot,” he said. “It’s either a giant ‘O’ of hope that he’ll do the right thing, or a symbolic house arrest.”

The activists said the pipeline would expose broad swaths of the United States to crude oil spills, while construction jobs would only be temporary and most of the oil would be shipped abroad with little impact on supply at home.