Some argue that because small states get more electors relative to their population than large states, the Electoral College is good for small states and protects their interests. However, that minor advantage is far outweighed by the incentives to ignore people who live in small states entirely when almost every state awards all of its electors to the winner of the statewide popular vote. From Ryan Cooper at The Week:
The 2016 candidates spent almost all their time in a handful of states, most of them medium or large. Two-thirds of campaign events happened in just six states — Florida, North Carolina, Pennsylvania, Ohio, Virginia, and Michigan. If we include Iowa, New Hampshire, Colorado, Nevada, Wisconsin, and Arizona, then those 12 states account for 96 percent of campaign events.
The nine smallest states (including D.C.), meanwhile, got precisely zero attention. Only the tenth-largest, New Hampshire, got any events at all. In total, 25 states (mostly small and medium-sized) got no events whatsoever. And while it's true the states that got huge attention are mostly on the big side, the very largest states were almost totally ignored as well — California and Texas got one event apiece, and New York none.
The reason for this is obvious. Almost every state gives all of its electoral votes to whoever wins the state — allowing candidates to take the votes of strongly partisan states for granted. Indeed, it's actively foolish to campaign where you are guaranteed to win or lose — only the swing states matter. It would be a waste of resources for a Democrat to campaign in California or Kentucky, or for a Republican to campaign in New York or D.C.