"I would like to thank J.K. Rowling for making this generous donation and for helping us in our work to make Britain a fairer and stronger country," The Times of London quoted Labor Party General Secretary Ray Collins as saying.
While Rowling is a close friend of Prime Minister Gordon Brown, the head of the Labor Party, the author said her donation was motivated by her belief in the political party's platform.
"I believe that poor and vulnerable families will fare much better under the Labor Party than they would under a Cameron-led Conservative Party," she said, referring to Conservative Party head David Cameron.
The Times said thanks to the success of the "Harry Potter" series, Rowling has an estimated net worth of more than $1 billion.
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