Only Labour benefit from first past the post

The fptp system is highly helpful to Labour for obvious reasons but it is much less helpful to the Tories. Fptp encourages tactical voting and we can understand why someone who dislikes the Tory party might feel inclined to vote for the Labour party to keep them out. The same does not happen so much in reverse. The tactical vote tends to be a punishment vote but people on the right do not tend to use elections to punish the other party... they have their own party to support and have no reason to punish people. To a Tory voting Tory is an endorsement of the status quo... they have no reason to 'punish' Labour. But this arrangement is very favourable to the Labour party because fptp elections tends to deliver victories for the centre-left. It is only the liberals who lose out in this arrangement. Fptp protects the Labour party from a liberal victory. So if the Tories support fptp we can deduce (if they are being logical) that they would prefer the Labour party to win than to have the liberals. Only the Labour party benefit from the fptp voting system. The Tories do not benefit from it because they receive very few tactical votes... they would not lose many votes in a switch to proportional representation. Only the Labour party would do significantly worse with pr... everyone else would do better which is why pr is to be welcomed. To support fptp is to support the Labour party because only they significantly benefit from it.