 accurate as interviewing everyone in the country. That's why pollsters talk about the margin of error. The term describes the biggest likely difference between results when polling, say, a random sample of 1,000 and if we talked with every American. Here's the general idea. Say a survey finds 52% favor candidate red and the error margin is plus or minus three percentage points. That means there's some chance as many as 55% back red, 52 plus three.