Polling 101: How to read polls in the last three weeks of the campaign

Each day at 1 p.m. EST, for the next 21 days until Election Day (Nov. 6), Gallop will update the results of its presidential tracking poll. If you’re not familiar with the poll, think of it less like box scores and more like the political health of each candidate. Reading medical charts requires years of education; understanding poll results takes a few minutes and basic math skills. You won’t even need a No. 2 pencil.