Could the Alamo have been won by holding out?

Could the defenders have won at the Alamo?

Only in a strategic sense: stronger preparations or a longer defence might have held Santa Anna's army until a relieving field force arrived.

The answer distinguishes tactical survival from strategic success. With several months of proper fortification, the position might have resisted more effectively, but 185 defenders in a partly fortified former mission could not reasonably destroy a force of roughly 3,500 with heavier guns. A more plausible form of victory would be to keep that army fixed at the Alamo until a Texian field force could arrive and engage it. The defenders would therefore win by buying operational time, even if they could not win the siege unaided. A delaying position can achieve its purpose without defeating the besieger outright.