good question , I think it if they start seeing erosions with more than one demographic group (not just women but other age groups ) of voters in these battleground states within their internal polling could be a deciding factor. I am pretty sure they are already looking at internal polling how the ticket compares with Harris /Kelly or Harris /Shapiro. They are polling these possible tickets mainly because Shapiro and Kelly have higher favorablity than the other Democratic candidates.
The other big factor that could play a major role would be if they start seeing decrease from large national super pac's .
Yes there would be some optics to be concerned if they did switch but this campaign has shown already nothing is out of the realm of being normal so far
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