I’ve heard claims that the Clinton campaign neglected either the Midwest or the “Rust Belt” in 2016, allowing Trump to win the presidential race even though Clinton won the plurality of votes.
Assuming that electioneering is a zero sum game, neglecting the Midwest means that they paid too much attention to other places. Maybe they were trying to win states they didn’t have a chance of winning, or were defending states that weren’t at risk of being lost, or assumed the battleground states were somewhere other than the Midwest, or were trying to help with congressional races.
Where did the Clinton presidential campaign neglect, and where did they pay too much attention, if the aim was to win the presidential race?
Basing answers on information only available after the election is fine, because I don’t know what information was available to the Clinton campaign during the race.