"To top the poll" means to receive the highest number of votes or to be the most popular choice among a group of people in an election or survey. Full definition
It is fast becoming an accepted position that they will in all likelihood top the polls in the 2014 European elections. (totalpolitics.com)
The first goal is to finish in the top two in the parliamentary ballots, even if that is a long way behind the candidate who tops the poll. (theconversation.com)
They face the real prospect that they could top the poll next month — and win not a single parliamentary seat next year. (yougov.co.uk)