Dogs don't vote in US elections. But what if they could? It all started with an Obama advisor tweeting a picture of the President with his dog Bo, a Portuguese water dog, in a car with this text: "This is how loving owners transport their dogs".
The reference was to a 2007 news story about the Romneys doing a 12-hour road trip to Canada with their Irish setter Seamus tied to the roof of their seven-seater van, in a carrier.
All the fresh air got to the poor pooch. It came down with the runs and soiled the van. Mitt Romney pulled over, hosed the car and the dog and hit the road, with Seamus back on the roof.
In a country where most families who can afford keep one or several dogs and treat them like their child -Michelle Obama calls Bo her third child - Romney had sinned gravely.
But has it hurt him? Though no one has polled that yet, Republicans gave away their unease by hitting back with their own poor-pooch story on Obama.
A Republican activist pulled out a para from Obama's autobiography in which he talks about trying dog meat as a youngster growing up in Indonesia.
Dog-meat eater Obama is looking no more angelic than Romney now. A Romney campaign aide re-tweeted to Obama camp's first tweet saying: "In hindsight, a chilling photo".
Think of this with the photo of Obama and Bo in the car.
Republican senator John McCain, weighed in on Thursday with this tweet: Pic of my son Jimmy's bulldog, Apollo - I'm sorry Mr. President, he's not on the menu!" Ouch!