politicians are criss-crossing the country wooing voters ahead of the election in 27 days ' time .
more than 25million live in constituencies where the result can already be predicted , because one party is so far ahead that there are 650 seats up for grabs on may 7 , with labour and the tories needing more than half to secure a majority .
however , the electoral reform society claims the result in 364 seats can be called now , based on current polls .