Not a problem at all. Just take an infinite number of possible combinations of matter and turn it loose over an indefinite period of time. Voila! Not only do we have a scientific explanation, but we can comfortably reject intelligent design as an unscientific notion that only serves insidously to insert religion into the educational process.
Two problems:
1.The earth is not infinitely old.
2. Life only comes from life. Life can't spring from non-life.