Public support for building the Keystone XL pipeline is consistent.  The Pew Research Center released the most recent polling on Sept. 26th.

Pew Research:

Most Americans (65%) continue to favor building the Keystone XL pipeline, perhaps the most politically contentious energy issue in Barack Obama’s second term. Yet when it comes to another issue making headlines – a proposal to tighten greenhouse gas emissions from power plants – the public favors stricter limits, by exactly the same margin as the Keystone pipeline (65% to 30%).

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Keystone XL Support Remains Broad

Support for the Keystone XL pipeline has remained fairly stable during the past six months (65% today, 66% in March), though opposition has risen from 23% to 30%.

During this period, the Obama administration has continued to weigh whether to allow completion of the pipeline, which would transport oil from Canada’s oil sands through the Midwest to refineries in Texas. Because the pipeline would cross an international border, the northern leg requires federal approval. The southern portion does not, and much of it has been constructed.

In June, President Obama for the first time linked the pipeline debate to climate change, saying he would approve the project only if it would not “significantly exacerbate the problem of carbon pollution.”

Republicans overwhelmingly support constructing the pipeline. Eight-in-ten conservative Republicans (84%) and 76% of GOP moderates and liberals favor building the pipeline. As was the case in March, Democrats are internally divided: By 58% to 41%, conservative and moderate Democrats favor construction of the pipeline. Liberal Democrats oppose the proposal, by 54% to 41%.

While majorities across all age groups back the Keystone XL pipeline, there is less support among young people. Among those younger than 30, 55% favor building the Keystone XL pipeline while 39% are opposed. People 30 and older favor it by more than two-to-one (67% to 28%).

The balance of opinion favoring the pipeline is roughly the same in the six states it would pass through as in other parts of the country. In the six states the pipeline would traverse – Montana, South Dakota, Nebraska, Kansas, Oklahoma and Texas – 69% support its construction while 28% are opposed. Those in other states support it by a margin of 64% to 31%