Executives at a number of firms across the country said in interviews that not only are more people willing to answer the phone to unknown callers these days, but that those who do agree to be interviewed are more likely to stay through the end of the conversation. This has led to an increase in productivity rates of roughly 25 percent, they said — and to an unusual situation where some respondents actually thank the pollsters for getting in touch.

It also means that, in a moment of crisis and in the midst of a presidential election, a wider variety of people are willing to tell pollsters what they think, so it’s more likely that a poll’s respondents will come closer to reflecting the makeup of the general population.

Even in online surveys, pollsters have also seen an increase in participation over the past few weeks. At the Pew Research Center, which does most of its polling through the online American Trends Panel, many respondents filled in a voluntary-comments box in a recent survey with expressions of gratitude.