I want to know the answer to the following question:
Whose recording of Hallelujah became successful again after being performed on American Idol?
All the background I'm provided with is that "Jason Castro's semi-final performance of "Hallelujah" also received considerable attention, and it propelled Jeff Buckley's version of the song to the top of the Billboard digital song chart.". Is that enough to answer the question?
Answer: yes