Cash in hand

The US is, nominally, a secular nation but has "In God We Trust" emblazoned on their banknotes.

The UK which has a state religion (Church of England) has on their banknotes:

• £5 Elizabeth Fry (prison reformer)
• £10 Charles Darwin
• £20 Adam Smith
• £50 John Houblon (Governor of the Bank of England)

Other fun tidbits:

• 92% of Americans believe that God exists or that God "probably" exists
• 26% of Americans think Evolution is true
• 38% of English believe in God
• 48% of English think Evolution is true
  

If atheists really wanted to gain some traction in the US, they should push for a state religion.