The British royal has topped a YouGov poll to find the nation's favoured next monarch.
People are said to have been pleased with the prince's appearance and speech at the Diamond Jubilee concert last Monday (June 4), as well as the way he joined his mother during the weekend's celebrations while Prince Philip remained in hospital.
A royal insider told The Express: "Charles has had his problems over the years with his image and getting his message across, but I think the public saw, and more importantly appreciated, the real Charles during the Diamond Jubilee celebrations."
Two weeks ago, a similar poll found Prince William had received 44% of people's votes to be the next king over Charles's 38%.
However, the new poll has reversed the figures.
The popularity of the Duke of Edinburgh has also seen a rise, with Prince Philip seeing an 11% increase in those who believe he is an asset to the royal family.
Piers Morgan recently stated that he believed Prince Charles would make a "great king".
Photo gallery - the Diamond Jubilee in pictures:
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