To the "Vote Blue No Matter Who" voters, it won't matter.
To the "Anyone But Trump" voters, it won't matter.
To the "Democracy Over Fascism" voters, it won't matter.
To the "Country Before Party" voters, it won't matter.
To the "Anti-Project 2025/Heritage Foundation" voters, it won't matter.
There are a lot of voters who are voting to reduce harm, strengthen/change the Supreme Court, recover/regain rights, etc. who will vote for anyone who isn't FPOTUS Trump. It's the Independents who may be squishy. It's the stay-at-home/leave it blank/write-in voters who may be a problem.
The DNC has to sell voting against all Republicans and the Republican plans laid out in Project 2025. The name on the ticket should not matter as much as the policies proposed by both parties. (I don't count RFK, Jr. in this discussion.)