Answer: the popularity of political candidates.
Step-by-step explanation:
Surveys in the 1800s were used in politics as a form of opinion polls to find out who the people thought would win in an upcoming election. The earliest known survey was done in July 1824 and was meant to find out the more popular candidate between Andrew Jackson and John Quincy Adams.
That survey was won by Andrew Jackson with a majority of 70% after which he went on to win the popular vote by a very narrow percentage but didn't become president as John Quincy Adams was voted in by Congress.