Several theories circulate about why Bill and Hillary Clinton named their daughter Chelsea. One is that they once enjoyed a visit to the Chelsea Flower Show, another that they were fond of the Joni Mitchell song "Chelsea Morning." Now we can add another theory: news that Hillary has invited Elvis Costello to headline at her 60th birthday bash later this month raises the tantalising possibility that the Clintons named their only child after Costello's 1978 hit "I Don't Want to go to Chelsea" (she was born two years later).
It is, perhaps, more believable than the official explanation – that Costello's presence will give Hillary a "younger, hipper, more fun" image. Costello is 53 and while his musical pedigree is impeccable – he's been called the David Attenborough of music because he "explores every nook and cranny that intrigues him" – "fun" isn't the obvious words that you would use to describe him. The political anger in many of Costello's songs is what gave him hero status to millions of disenchanted students in the 1970s and 1980s.
But the man who started off as a geeky genius in NHS specs, the new-wave answer to Bob Dylan, has always been quietly cool. Perhaps this is the effect Mrs Clinton is looking for. We must wait and see whether she will ask him to sing "Tramp the Dirt Down," in which he looks forward to the death of Baroness Thatcher. Neither Elvis nor Costello are his real names. He was born Declan Patrick MacManus in West London where his father was a singer and jazz trumpet player and his mother worked at Selfridges. The family moved to Liverpool when he was a young schoolboy and, after leaving school at 18, he worked for a time as a computer operator.
Like his father, he loved music and became a folk singer touring pubs in a band called Flip which broke up in 1975. Using his mother's maiden name he became Elvis Costello and signed to Stiff Records in 1977. His first hit with The Attractions was "Watching the Detectives" that same year. Within less than five years he was being called Britain's leading songwriter and had unequivocally earned the status of "national treasure".
Costello has been married three times, first to Mary Burgoyne in 1974, with whom he had a son, then in 1986 to Cait O'Riordan, then bassist for The Pogues, and in 2003 to the Canadian singer, Diana Krall. Last year the couple, who live in New York, had twin sons. "I'm definitely, unashamedly happy," he has said with un-Costello-like joy.
But Costello has always remained true to his belief that his music must keep developing. "I don't want to be defined by a handful of songs I wrote 25 years ago," he says.
Indeed he had been ready to quit in 1979. "It's an empty thing to just have a bunch of uncomprehending teenagers waiting for you to sing 'Oliver's Army' because that's what they've seen on Top of the Pops," he said at the time. Any of Mrs Clinton's party guests thinking of a nostalgic request, please note.