Since the Billboard Hot 100 chart pretty much became obsolete in terms of tracking radio success, the radio&records/mediabase chart is the one that truly reflects national airplay. Such has been the case since soundscan took over and bastardized Billboard back in December, 1991.
In the late 90's, for all intents and purposes, the pop chart split into two separate charts: the classic CHR (contemporary hit radio) chart which had always been the pop chart AND the HOT AC chart (adult top 40) which is pretty much the pop chart for people over 18.
POP:
Kelly Clarkson:
Miss Independent: #1 for 5 weeks
Because of You: #1 for 1 week
Since U Been Gone: #1 for 7 weeks
Break Away: #1 for 1 week
Behind These Hazel Eyes: #2 for 8 weeks
A Moment Like This: #4
Walk Away: #5
Chris Daughtry:
It's Not Over: currently #4
No other AI alum has ever hit the top 10 (although both Clay Aiken and Kimberly Locke hit the top 20)
HOT AC:
Kelly Clarkson:
Miss Independent: #14
Since U Been Gone: #2
Break Away: #2
Because of You: #2
Behind These Hazel Eyes: #1
Walk Away: #3
Chris Daughtry:
It's Not Over: #1 for 1 week (the new #1)
While Kelly's chart success has been astronomically dominating, congrats to Chris for the second most successful radio career of any AI-er.



