When your own coalition is proving stubbornly hard to grow, you have to subtract from the other person's. https://t.co/vZqWpdljue— Maggie Haberman (@maggieNYT) April 8, 2020
To begin with, "Vote Against" is a terrible campaign strategy. It was that strategy that let Trump win in the electoral college because so many people refused to vote for Hillary, but were sure the rest of us would "vote against" Trump. And besides, as the double elections of W proved, "vote against" is not a strategy that turns out the votes for your candidate. Ever.
So this is a loser's strategy to begin with.
OTOH, in a "vote against" campaign (which Biden is smart enough not to run), who is more likely to be the candidate people turn out to reject?