The recent slide in oil prices to four-year lows is throwing another question mark into the six-year saga surrounding the Keystone XL pipeline, with arguments being made on both sides as the Republican-controlled House approved the project again in a vote on Friday.
For the first time ever, the Democrat-controlled Senate has relented and also plans to vote on the proposed line running from Alberta, Canada, to Nebraska next week.
Kevin Book, head of research at Washington, D.C.-based ClearView Energy Partners, told CNBC on Friday the pipeline is needed more than ever to support the growth in U.S. oil production in the Bakken region of Montana and North Dakota. ClearView provides energy policy insights to institutional investors and corporate strategists.
"As you get lower and lower on crude, you have a bigger differential from transportation costs," Book said in a "Squawk Box" interview. "At $90 a barrel, taking a train to the Gulf of Mexico [was] not such a big deal. At $75 a barrel, plus the quality differential for oil sands downward, suddenly you want that pipeline."