Several Democratic presidential candidates – including Elizabeth Warren, Bernie Sanders and Kamala Harris – are vowing to ban fracking if elected. But they wouldn’t be able to do so under a bill introduced by Republican U-S Senator Pat Toomey. Toomey has introduced a resolution re-affirming that presidents cannot unilaterally ban fracking on state and private land. Last month, Democratic Senator Bob Casey and Democratic Congressman Conor Lamb said that the Democratic contenders should reconsider their threats to ban fracking if they ever hope to win over Western Pennsylvania voters.