In the first campaign I was paid to work on, a long-time politico advised me not to have my candidate doorbell every home in a neighborhood: "if you're going to hit every home, you might as well go doorbell in Hawaii. The weather is nicer, and they can't vote for you there, either."
The point is that doorbelling every home means you're talking to residents who aren't registered voters or who have registered but haven't voted in decades. You're also talking to partisans who would never vote for you.
Stefan Hankin with Lincoln Park Strategies makes this point in more detail here in Campaigns & Elections magazine this week, using Hillary Clinton's campaign strategy as an example. Check out his piece and heed his advice: go where the fish are biting.
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