Keep in mind that although Virginia always had a greater population than West Virginia that after the poll tax was passed in Virginia in 1902, West Virginia would start casting far more votes than Virginia until the Civil Rights Era. The regional rivalries would have been phenomenal.
Given the people who were running Virginia at that time, they would have modified the poll tax to also explicitly target poor white people in WV. With this in mind, and coal not being an all-or-nothing industry in the larger state of VA, I don't think the Depression-era union activism in WV ever really takes off to the point of any statewide power (it didn't in any other Southern states with coastlines). So the WV part of larger VA probably never goes Dem in the first place.
