Taylor Swift is extremely busy right now, especially on the Billboard charts. She's currently promoting two singles from two different albums, and both are doing very well. Her single "Karma" is currently at No. 2 on the Pop Airplay chart, and if it can reach No. 1, she will tie with three other artists for the most leaders in the history of the chart.

The only thing standing in Swift's way is Selena Gomez's song "Calm Down." The track, which is fronted by Afrobeats star Rema and which jumped up the Billboard charts after Gomez joined, has been slowly but steadily climbing for months. It is currently in charge of the Pop Airplay chart for a fourth non-consecutive frame.

Eventually, "Calm Down" will begin to descend on the chart, but it is unclear how long it will take for the tune to give up the top spot. If that happens soon, Swift will likely be able to take over with “Karma.” But, if it takes weeks or even months, interest may shift to Swift's other single, "Cruel Summer."

"Cruel Summer" is also climbing the Pop Airplay chart, and this week, it is up to No. 14. If radio DJs change their focus, "Karma" may end up stalling in the runner-up spot while "Cruel Summer" improves its standing. In that case, neither track may end up ruling, if the stars don’t align for the Grammy winner.

Of course, it is also possible that "Karma" will take over the Pop Airplay chart for a while and then descend, making way for "Cruel Summer" to eventually take over. Swift is a darling of the radio waves, and with interest in her Lover song renewed and hotter than ever, anything is possible.