1. You would need a voltage regulator with less than 70 mV of minimum headroom. Possible, but very difficult.
2. 70 mV is less than 2% of 3.6 V. As such, it is less than the standard voltage tolerance for the vast majority of voltage regulator devices, and well within the operating voltage range of most low voltage ICs. Whatever is running on the 3.6 V will be fine without any need for a regulator circuit.
Of course, this would be much easier to answer if you would share information about the circuits you are using. Have you read the datasheets regarding the operating voltage ranges? It is important to note that the operating voltage *never* is a single, absolute number. It always is a range of values, with +/-5% a very common range.
ak