Exxon has supported a carbon tax since at least 2009. The idea has also drawn support from some prominent conservatives, including economist Arthur Laffer and former George W. Bush economic adviser Gregory Mankiw.
Former South Carolina Republican Rep. Bob Inglis founded a group that is pushing for a carbon tax, which would be offset by a lower income tax.
Last month, the conservative American Enterprise Institute co-hosted an event with the Brookings Institution, the International Monetary Fund and Resources for the Future about the economics of carbon taxes. The event included a keynote speaker from the Obama Treasury Department.