The right wings of both main parties are now effectively separate parties in themselves.
Each owes allegiance to a former Prime Minister. One of those Prime Ministers is dead. The other is the living dead.
The opinion polls were right. If last year's General Election had been conducted according to electoral law, then there would indeed have been a hung Parliament.
In 2020, there will be a hung Parliament, or (not very probably) a Conservative overall majority on paper but dwarfed by the size of that Thatchobite Party, or a Labour overall majority on paper but severely tested by the size of that Blairobite Party.
In any of those circumstances, even one MP could exercise very considerable influence. If that MP were of sufficiently definite views and character.