The poll, conducted by YouGov, found 45 percent saying they supported Justice Secretary Kenny MacAskill's decision to free Megrahi, who has terminal cancer, on compassionate grounds, The Glasgow Herald reported. The same percentage said MacAskill was wrong.
A poll last week for the BBC showed only 32 percent of Scots said they supported MacAskill's decision.
"The poll demonstrates a very substantial shift of opinion towards support for the justice secretary's decision," a MacAskill spokesman said.
YouGov surveyed 1,556 people for the new poll, done for the Scottish National Party.
Almost half, 49 percent, said the support of Nelson Mandela, the revered former president of South Africa, for Megrahi's release had increased Scotland's international standing. One-quarter said the release had hurt Scotland internationally.
Megrahi's release and the warm welcome he received when he returned to Libya provoked outrage in the United States and in some quarters in Britain.