"In the winter of 2019–2020, about 5.5 million households in the United States used heating oil (distillate fuel oil) as their main space heating fuel"
https://www.eia.gov/energyexplained/heating-oil/use-of-heating-oil.php
Since those homes are primarily in five states PA, NY, ME, MA, & CT politicians don't have to worry about losing voters in those states. The sheep will continue to vote D, except perhaps for Pennsylvania, maybe. PA sometimes votes republican.