John Mayer feat. Taylor Swift – “Half of My Heart” – (2009)

Well 2009 is officially over five years ago, so I can feature songs from that year. And this duet between John Mayer and Taylor Swift gained significant radio popularity in the first half of 2010. It peaked at #25 on the Hot 100 and its best performance was on the Adult Top 40 chart, where it reached #2. This is the kind of song the Adult Contemporary crowd loves.