The Whale and Dolphin Conservation Society (WDCS) will be the first charity to run an online raffle on MSN UK, one of the country's leading internet portals.
MSN UK's 1.1 million monthly visitors will be encouraged to enter the WDCS online raffle, which will appear on the portal's competition page.
Charity Technology Trust, the technology charity that organises online raffles and competitions for a range of charities, brokered a deal with the portal which will see a range of UK charities run similar initiatives to raise funds and drive people through to their web sites.
Peter Sweatman, chief executive of Charity Technology Trust, said: "It's easier to get someone to enter a raffle than donate straight to the cause, and attractive competitions are a good way of introducing new people to a charity.
"One of the hardest things for a charity to do is increase traffic and donations to its web site, and we hope that mechanisms like online competitions and raffles go some way to achieve this goal," he said.
The MSN raffle is similar to one run by Charity Technology Trust on WDCS's web site, www.wdcs.org.uk.
Prizes, including a whale-watching holiday to the Azores, have been adapted to appeal to a wider audience who may not be familiar with the charity's work. Participants can purchase virtual tickets for the raffle for 50p each, with all proceeds going directly to the WDCS.