Daily Star: Jerry Lawton

Bookmakers predict bets totalling £650million will be placed over the three-day meeting, which starts today.

And £300m is expected to be wagered on the big race itself, which will be watched by a worldwide TV audience of 600m.

That will be the most bet on a horse race anywhere in the world.

Punters are queuing up to back last year’s champion Tiger Roll to become the first horse since Red Rum in 1974 to win two on the trot. 

The horse – which won by 22 lengths at Cheltenham – is set to start the shortest-priced favourite in the history of the race.

On top of that, the races switch from Channel 4 to ITV and later 5.15pm start time – after most football matches have finished – are expected to give it a further boost.

Bookies expect one in four Brits to place at least one bet on the race.

Course bosses expect 150,000 people at Aintree, Liverpool, over the next three days.

They will sup 300,000 pints, 8,000 bottles of champagne and up to 25,000 cocktails cooled by 1,813,000 ice cubes.

For the first time, the winning owner will celebrate with Coates & Seely English sparkling wine instead of French bubbly.

Paul Binfield, of Paddy Power, said: “This year’s National has been the most popular for ages. It’s the draw of Tiger Roll .”

Nicola McGeady, of Ladbrokes, said: “All betting records are expected to be torn up on Grand National day.”