The Wizard Of Oz track which has had a surge of popularity in the wake of Baroness Thatcher's death is on course for a place in the top five.
An online campaign has driven sales of Ding Dong The Witch Is Dead, and the latest placings released by the Official Charts Company show it had sold 20,000 copies up to last night and is now at number four.
The late former prime minister divided opinion and while many have mourned, some have seen her death as a cause for celebration, prompting a download surge for the song.
The chart position includes sales of all the versions of the song from the 1939 film recording, while a separate cover version by Ella Fitzgerald from 1961 is currently outside the top 75.
The song is also on course to become the shortest top 10 single ever, with the most popular version running to 51 seconds.
The BBC said it would decide whether to play the track during Radio 1's top 40 countdown when places are finalised at the weekend.
It said: "The Official Chart Show on Sunday is a historical and factual account of what the British public has been buying and we will make a decision about playing it when the final chart positions are clear."