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Even the random sampling that was once standard has given way to a nonprobability sampling approach based on increasingly specific population proportions. So, if 6% of a population are Black men with a certain level of education and a certain amount of household income, then a survey will strive to have 6% of its respondents match those characteristics.

In quota sampling, participants may not be selected randomly but rather chosen as participants because they have specific demographic attributes. This method is less statistically rigorous and more prone to bias, though it may yield a representative sample with relative efficiency. By contrast, stratified sampling randomly selects participants within defined groups, reducing sampling error and providing more precise estimates of population characteristics.

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A newer technique pollsters are using to reach respondents is something called river sampling, an online method in which individuals encounter a survey during their regular internet browsing and social media activity, often through an ad or pop-up. They complete a short screening questionnaire and are then invited to join a survey opt-in panel whose members will be asked to take future surveys.

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Instead, like most modern pollsters, we (Emerson College Polling) use a mix of approaches, including text-to-web surveys, interactive voice response on landlines, email outreach, and opt-in panels. This combination allows us to reach a broader, more representative audience, which is essential for accurate polling in today's fragmented social and media landscape. This diverse population includes younger individuals who communicate through various platforms distinct from those used by older generations.

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