"There are 47% who are with him [Mr Obama], who are dependent upon government, who believe that they are victims, who believe the government has a responsibility to care for them, who believe that they are entitled to health care, to food, to housing, to you-name-it," he said.
Mr Romney said in the video that his role "is not to worry about those people. I'll never convince them they should take personal responsibility and care for their lives."
The video clips provided to Mother Jones are said to have been filmed at a $50,000 (£31,000) per head fundraiser at some point after Mr Romney became the presumptive Republican nominee.
They were made public as the Romney campaign announced a new shift in strategy after several difficult days for the candidate.