Strikes me it's be simpler to just use the names of the parties' totem animals, and say it's a fight between the Elephants and the Donkeys.

Has Nader got a totem animal? Buffalo? Turkey? Porcupine?

I think having totem animals for parties is a great idea. If they had them for the parties in England right now, I'd say a dead parrot for the Tories. And a live parrot for Labour.