Daenerys definitely fits the criteria to become Azor Ahai. Early on in season seven, Missandei notes that the High Valyrian phrase "The Prince That Was Promised" is technically nongendered. A better (albeit clunkier) translation of the prophetic phrase would therefore be something more like, "The Prince or Princess That Was Promised." With such a direct nod to Dany's possibility as a candidate, we have to consider the probability.
And, well, let's just say the probability is very high. Let's look back at that phrase again: "When the red star bleeds and the darkness gathers, Azor Ahai shall be born again amidst smoke and salt to wake dragons out of stone." All of these bases are covered in one pivotal scene: Dany's miracle with Khal Drogo's funeral pyre at the end of season two. The aforementioned Red Comet appears in the sky as night falls, and Daenerys walks into the flames of the pyre with her dragon eggs. She walks back out, having "awoken" her dragons from the "stones," with the smoke having been the pyre. Perhaps the "salt" is the tears she shed over her love's death.
Daenerys has proven she's immune to fire, so really, at this point, she just needs to find her Lightbringer to take it all home. And seeing as her prophecy from the House of the Undying predicts her death anyway, it would all make perfect sense. Daenerys could become Azor Ahai and destroy the White Walkers as her last valiant act.
