Reeve, who filmed the ad shortly before his death on October 10, has already featured in the US ads after his family gave approval last week.
Reeve says in the 30-second ad: "Stem cells have already cured paralysis in animals. Stem cells are the future of medicine. Please support Proposition 71 and stand up for those that can't."
Supporters of Proposition 71, including Silicon Valley entrepreneurs and investment capitalists, have invested over $27m on a widespread TV ad campaign.
'Back to the Future' and 'Spin City' actor Michael J Fox, who suffers from Parkinson's disease, also featured in a recent campaign.
In comparison, the coalition against Proposition 71 have spent $260,000 on commercials opposing stem cell research.
Dana Reeve, the actor's widow, has already pledged her support for Democratic candidate John F Kerry, who is planning to back funding for stem cell research if he wins the Presidential election on November 2.
Reeve, who starred in four 'Superman' films, was paralysed from the neck down in a horse riding accident in 1995. He died, aged 52, from heart failure brought on by his condition.
Reeve was also chairman of the Christopher Reeve Paralysis Foundation, a US non-profit organisation set up in 1999 to support research to develop effective treatments and a cure for paralysis caused by spinal cord injury and other central nervous system disorders.
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