Most polls suggested Labour would win, which may have encouraged wavering, undecided voters to back the then Conservative government out of fear of a Labour administration led by Neil Kinnock
2015 general election
The closeness of the polls led to Conservative efforts to warn about the possibility of a Labour-SNP coalition, which may have helped shift the election in favour of a small Tory majority
Polls showed that Immigration as an important issue to voters after 2010

Successive Conservative pledges to limit net migration to the 'tens of thousands'
