A quick search brought up this study -
To find the states with the most and least influential voters, WalletHub calculated the number of elected officials in the federal government per total number of adult residents in each state during the current midterm election year. The calculation methods we used for this study resulted in three key metrics, which are described below, along with their corresponding weights. The higher the ratio for each, the more powerful the voters were or will be in the elections. We also gave double weight to those particular races where a tossup is anticipated (regardless if they were for senate, house or gubernatorial).https://wallethub.com/edu/how-much-i...2/#methodologyFor this particular study, we counted only the population aged 18 or older. While elected state officials represent everyone in their states, the purpose of this study is to rank the relative influence of voters across states. However, our data was not able to account for the limited number of state laws that allow 17-year-old residents to vote and/or bar prisoners or felons from doing so.
- Senate Elections – Full Weight: Number of Senators in Each State/Projected Population Aged 18 or Older in 2018
- House Elections – Full Weight: Number of Representatives in Each State/Projected Population Aged 18 or Older in 2018
- Gubernatorial Elections – Full Weight: Governor /Projected Population Aged 18 or Older in 2018
Sources: Data used to create these rankings is courtesy of the U.S. Census Bureau.
All the steps in the methodology seem reasonable (though personally I don’t like the doubling weight for tossup races), and with or without that quibble I think the picture is clear - a votes worth is very much dependent on where they are in the country.