Entrance poll
An entrance poll is a poll that is taken before voters have cast their votes at the polling stations. It is akin to an opinion poll in the sense that it asks who the voter plans to vote for or some similar set of questions. The possibility that the prospective voter might change his mind after the poll is very small compared to that of an opinion poll, therefore the margin of error of an entrance poll is expected to be lower than that of an opinion poll. However, the methodology of conducting an entrance poll is closer to that of an exit poll, where actual voters are being queried as opposed to potential voters in an opinion poll.
Entrance poll result estimates can be obtained very quickly as people can be interviewed earlier and more quickly, as opposed to exit polls. However, these polls are possibly subject to higher margins of errors compared to exit polls as early voters are given a higher preference than in exit polls.
Entrance polls are based upon a future event, There is always the possibility that a voter will change his or her mind between being asked questions for an entrance poll and then actually voting. Entrance polls can be used in predicting the outcome of an election that is underway. [1][2] 2008 Presidential Entrance poll Iowa Caucus = Entrance polling results from the Iowa caucuses show about 45% Democrats are first-time attendees, while about 55% said they had attended before. On the Republican side, about 45% early arrivers say this is their first caucus, a bit more than said so in 2012.The entrance polls suggest that although we're seeing tight races on both sides, only the Democrats are showing demographic rifts.