Does a hit song have to give ’em the old razzle dazzle in Chicago or join Meat Loaf in search of paradise by the dashboard light?

Does Beyonce need to check on it, or can it simply walk the line to success with Johnny and June?

The mystery of what makes a hit has perplexed song writers and marketers for as long as there has been popular music.

And in the end, the next hit song may be unpredictable.

But a new study has come up with an intriguing clue: People will select a song if they think others like it.

In other words, at least one key to musical success is the buzz, or bandwagon effect.

The same is true for books and other products, says Duncan J. Watts, an author of the study appearing in Friday’s issue of the journal Science. “Successful things tend to be more successful,” he says.

Once an author has a best seller, the next book he writes is likely to also become a best seller, and once a brand name has recognition it is more likely to do well.

The possibility that musical popularity may be unpredictable could, in a way, be comforting to music marketers, said Watts, a sociology professor at Columbia University.

“The fact they have such difficulty predicting what’s going to be popular doesn’t mean they are incompetent,” he said. “There are all these stories of famous acts that weren’t picked up by someone,” he noted. “It’s just inherently unpredictable.”

“The [study] results are certainly consistent with the motivations for payola. . Getting it out there and getting it on people’s radar screens increases its likelihood of it becoming popular,” said Watts. Payola involved marketers bribing disc jockeys to give their records more air time.

In their search for what makes a song a hit, Watts and his colleagues recruited 14,341 participants, asking them to listen to and rate popular music