Saturday’s Virtual Grand National raised more than £2.6m for NHS Charities Together.
The computer-simulated event, staged after the actual race was cancelled because of the coronavirus pandemic, was "won" by 18-1 shot Potters Corner.
Bookmakers paid out on the "winner" and are donating profits from losing bets.
The event had a peak television audience of 4.8m - 30% of the audience - on ITV, with an average figure of 4.3m during the 30-minute broadcast.
Christian Williams, trainer of Potters Corner, told BBC Sport he and his family were cheering on during the race.
“There was great excitement in the house,” said Williams. “The children were on their toy horses and it was great watching the race and seeing our horse come through to win.”
All horse racing in Great Britain has been suspended until at least the end of April.
Forty runners who would have been most likely to line up at Aintree took part in the Virtual Grand National, using CGI technology and special algorithms.
Where they finished
- 1st - Potters Corner 18-1
- 2nd - Walk In The Mill 16-1
- 3rd - Any Second Now 10-1
- 4th - Tiger Roll 5-1
- 5th - Burrows Saint 12-1