How would the UK fare in a war against France?

Some basic figures to save you time are printed below.

Population:

UK: 60,776,238 (15-64 years: 67% (male 20,605,031)
FRA: 63,713,926 (15-64 years: 65.2% (male 20,798,889)

Wealth and Defence Spending:

UK GDP: $2.346 trillion (2006 est.). Percentage of GDP spent on defence: 2.4%.
FRA GDP: $2.151 trillion (2006 est.). Percentage of GDP spent on defence: 2.6%.

Thanks to the CIA for the figures.

It’s safe to assume that both countries are capable of manufacturing everything they need to fight a war, as long as the raw materials are available of course. It is also safe to assume, in my opinion that the UK’s island status makes it a more formidable foe to defeat, while limiting its ability to project its power. An example being Hitler’s futile attempt with Barbarossa, and the sheer number of soldiers needed to take Normandy later on.

I don’t want this to turn into a white flag factory versus tea drinker’s idiot fest, so can we leave the stereotypes at the door please. It’s a war gaming exercise.

The odds seem equal to me, so what is the determining factor that sways the battle?