He'd do worse than Astorino did.
He'd do better actually. Pataki had three term experience and was known to be more liberal on social issues than the national GOP. Even in 2006 he said that he would consider the state government recongize gay marriage performed in Massachusetts. And was known to be closer to the democrats on abortion way back in 1994.
gay marriage even in 2006 was not as accepted until the last half decade.
But given the demographics in New York that has made the state more loopsided in favor of the democrats he'd have to pray that he'd get close.
Its likely that Cuomo compared to this year would go left just like Quinn did against rauner, and Hawkins drops out just like the greens in illinois did to help quinn.
Then edge out a narrow victory. but Pataki probably gets 70-85% support in Upstate, wins the suburbs by 55-70%. But still lose because of NYC.