After a five-year battle, TransCanada Corp. may be close to winning approval for its $5.3 billion Keystone XL pipeline, which will transport crude oil from the oil sands of Alberta to Steele City, Neb., 1,179 miles away.

It’s the last leg of a mega pipeline that leads to the Gulf Coast, and the project has been deeply controversial, pitting environmentalists and some landowners against proponents who argue that it will provide a secure source of energy and boost the U.S. economy.