For example, this
story from 2000 claims that Bush was on the "wrong side" of a gender gap due to trailing his overall numbers among women. Another example is this recent
PPP blog post which calls Democrats the "beneficiaries of a gender gap", although it's not as bad because it does mention how men favour Republicans.
However, you could just as easily claim that Gore was the wrong side due to trailing his overall numbers among men. The fact of the matter is:
all over-performances among some group or groups must be matched by under-performances among some other group or groups. Sort of like Newton's Third Law. Yet whenever I see the gender gap analysed, it's always treated as if this benefits Democrats. Why is this so? Is there some subconscious sexism, the idea that men are treated as the "default" group and so we think of the "male vote" as being roughly synonymous with the overall vote, but the "female vote" as a separate category?
We also see this with race, although there is less consensus on who "benefits". I can't find the full article, but here's some
excerpts of one that talks about how whites gave a majority of their vote to John McCain. Yet clearly, if a candidate does extremely well relative to their national margins among minorities, it is necessary for that candidate to do relatively poorly among whites. If that meant the candidate still won whites, that means the candidate must have won in a landslide. With political competition as it is, landslides can't be sustainable.