The suspense is well-nigh unbearable. Will it be Volare, crooned by Domenico Modugno of Italy in 1958, or Ein bisschen Frieden, Nicole's unforgettable (if near-incomprehensible) winner of 1982?

Poupée de cire, poupée de son, France Gall's catchy little number from 1965, could sneak through on the back of a strong French-language turnout, while the Olsen Brothers might conceivably benefit from a home advantage with their Fly on the Wings of Love (2000).

But the smart money in tonight's 50th anniversary Eurovision Song Contest show, broadcast live from Copenhagen to more than 25 countries (although not, sadly, Britain), is on Abba's 1974 smash Waterloo, being quoted by London bookies at around three to one. "It's the one just about everyone has heard of," said a spokewoman for the organisers, Danmarks Radio.

Viewers who tune into the the two-hour spectacular, hosted by Katrina Leskanich from Katrina and the Waves, who won in 1987 with Love Shine a Light, and Latvia's Renars Kaupers, who came third in 2000 with his band Brainstorm, can help to choose the best Eurovision song from a shortlist of 14 selected from an internet vote. Others in with a shout are Sir Cliff Richard's Congratulations (1968), What's Another Year and Hold Me Now by two-time Irish winner Johnny Logan, and Brotherhood of Man's Save Your Kisses For Me (1976).

The show will feature original videos of the 14 songs, "complemented by dancers and visual effects". The highlight, said Danmarks Radio producer Soren Therkelsen, would be an appearance by the first winner, Switzerland's Lys Assia, who triumphed in 1956.