Video report by ITV News Correspondent Richard Pallot
With the help of his walking frame, Captain Tom Moore is aiming to complete 100 lengths of his 25m-long back garden before he turns 100 at the end of April.
He had hoped to raise £1,000 for NHS Charities Together but has since smashed his original target.
Mr Moore tweeted: “WOW WOW WOW. 1.5 million pounds for our amazing NHS.
“I am blown away by the Great British public and their generosity!
“You are all so amazing and showing what is so special about our great Nation. Thank you.”
Mr Moore was born in Keighley, West Yorkshire, and trained as a civil engineer before enlisting in the army for World War II, where to rose to the rank of a captain and served in India and Burma.
A host of celebrities have left personalised messages in support of Captain Moore's fundraising campaign, including Anton DuBeke, Jason Donovan and Ian Poulter.
Good Morning Britain host Piers Morgan and BBC Breakfast host Dan Walker also tweeted their support for Captain Moore.
Maytrix Group, which is donating £1 for every length Tom completes, added: “Thank you - and a huge thank you to our NHS at this terribly sad time in the country.
“We are behind you every step.”
A link to Captain Moore's fundraising campaign is here.
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