Environmentalists may have lost their monthslong battle against the Dakota Access oil pipeline, but their war against the oil and natural gas industry is far from over.

Not only are groups including Sierra Club joining forces and renewing their efforts to take down TransCanada Corp.'s Keystone XL line, a project that now has the State Department's blessing to carry Canada's oil to the Gulf Coast. They're also taking advantage of 300,000 new supporters and a surge in donations made to fight Dakota Access and Keystone to target smaller pipelines that were under the radar.

"We do plan to double down on Keystone, and we plan to use Keystone as a launching point to change a lot of hearts and minds and to fight multiple other projects at once," said Sara Shor, a campaign manager at the New York-based environmental group 350.org.

President Donald Trump's backing of the Dakota Access and Keystone pipelines has energized what activists say is a more organized, formidable opposition that's hungrier for battles than ever. The arsenal includes legal challenges, public pressure on banks to withdraw financing and targeted lobbying of regulators and lawmakers.

"The community of groups fighting these projects are getting creative, recognizing that the oil and gas industry does have a friend in the White House," said the Sierra Club's Lena Moffitt.

Among pipelines they aim to target are Keystone; Dominion Resources Inc.'s $5 billion, 564-mile Atlantic Coast pipeline, and Energy Transfer Partners LP's expansion of the Bayou Bridge line that delivers oil to Louisiana.

First they'll go after the projects' financiers — a strategy that's already proven somewhat successful in the fight against Dakota Access and coal projects. Greenpeace circulated a petition to lobby banks against funding Keystone on the same day the State Department approved it.

Then they'll fight in court. A coalition has asked the U.S. Court of Appeals to block Williams Cos.'Atlantic Sunrise gas line in Pennsylvania, arguing that federal regulators cut corners in their review.

Williams spokesman Chris Stockton said the action "reeks of desperation," and would only delay much-needed energy infrastructure.

On Thursday, a coalition led by the Sierra Club filed a lawsuit in U.S. District Court in Great Falls, Mont., challenging the State Department's permit for Keystone. That followed a similar filing Monday by the Indigenous Environmental Network in the same court.

Groups are also orchestrating more targeted protests at agencies at the local, state and federal levels. "Projects used to go unopposed, and now they're facing intense grass roots resistance at every level, and that will only continue to intensify," Shor said.