Just over a quarter of the motorists 1000 quizzed by the charity - 26 per cent - said they were happy for the limit to stay as it is now.
Motorists also said they wanted to see much tougher penalties for drivers who repeatedly flout drink-drive laws.
Some 95 per cent said tougher penalties were needed for motorists found drunk behind the wheel, while 89 per cent favoured "alcolocks", which fit into vehicles to prevent drivers turning the car on while inebriated.
Brake now is calling on politicians to commit to a 20mg limit in their general election manifestos.
The current drink-drive limit in England and Wales sends a confusing message and asks drivers to do the impossible - guess when they are under the limit, and guess when they are safe to drive.
In reality, even very small amounts of alcohol impair driving, so the only safe choice is not to drink at all before driving. The law needs to make that crystal clear.
However, ministers say the government is already taking steps to tighten drink-driving laws, and take drunk motorists off the road for longer.
Britain already has tough penalties to tackle drink-driving and the Government believes increased enforcement is a more effective deterrent than a change in the law.
We are removing the automatic right for drivers who fail a breathalyser test to demand a blood and urine test. High-risk offenders are now also required to prove they are no longer alcohol-dependent before being allowed to drive.