The prospect of Elizabeth Warren becoming the 2020 Democratic presidential nominee, or the 46th president of the United States, has energy investors worrying about risks to hydraulic fracturing.

“What happens if Elizabeth Warren becomes president and bans fraccing?” was the most common question Sanford C. Bernstein received during recent marketing, analysts led by Bob Brackett said in note Tuesday. They don’t currently have a good answer.

Concern on Wall Street has been rising along with 2020 Democratic presidential contender Elizabeth Warren’s poll numbers, with sectors such as financials, health care and industrials as well as energy identified among those at risk from her policy proposals.

In early September, Warren tweeted: “On my first day as president, I will sign an executive order that puts a total moratorium on all new fossil fuel leases for drilling offshore and on public lands. And I will ban fracking—everywhere.”

The former part of Warren’s plan would have a modest longer-term impact given the “mature state” of areas such as onshore Alaska or the Federal Gulf of Mexico, according to Bernstein. However, a fracking ban would offer “much more immediate consequences,” and be “incredibly bullish for both global oil prices and U.S. natural gas prices.”

Federal leasing changes could have the most impact on shale drillers such as EOG Resources Inc. and Devon Energy Corp., Brackett said. Kosmos Energy, Hess Corp., Apache Corp. and ConocoPhillips may have little to worry about from a fracking ban, however.

Still, any impact from a Warren win may be short-lived. “We have a government with checks and balances,” Brackett noted, pointing to processes which have caused executive orders to be moderated. He also highlighted the ability of E&Ps to re-allocate capital to mitigate effects.

And, as RBC Capital Markets wrote earlier this week, most of the sectors seen to be at high risk “are already deeply undervalued versus the broader market.”

There may also be some beneficiaries. UBS analyst Lloyd Byrne recently identified Canadian producers such as Canadian Natural Resources Ltd and Suncor Energy Inc as likely to gain from the curbing of drilling on federal acreage.