Foes of the proposed Keystone XL oil sands pipeline – including billionaire climate activist Tom Steyer – will roll out a campaign pressuring President Obama to reject the project.

The goal: Get Obama’s core supporters to make their case to the president. The social media campaign will focus on “rallying support from President Barack Obama’s online supporters, including the membership of Organizing For America [OFA],” an advisory states.

The OFA is the group borne from Obama’s reelection campaign that advocates for his agenda, and Keystone foes are targeting the pro-Obama group as part of the work against TransCanada Corp.’s proposed pipeline.