"The emerging optimism is encouraging, but the disparity in optimism between the non-retired and retired is notable. The lack of action on the part of investors during the first quarter rally shows that people stayed the course and didn't have a knee-jerk reaction that caused them to change their investment allocations," said Laurie Nordquist, director of Wells Fargo Institutional Retirement and Trust.

Half of retired investors surveyed between March 14-24 say low interest rates have done a great deal or quite a lot of harm to savers and investors compared to 25 percent of non-retired investors. Nearly 70 percent of non-retired investors believe the benefits of low interest rates have outweighed the costs, but only 51 percent of retirees agree with them.

Nearly half of all investors believe that today's low interest rates will make their retirements less comfortable, with 35 percent of retirees and 46 percent of workers fearing low rates will mean they will outlive their money in retirement. One-third of investors think low rates will force them to delay their retirement.

Housing is one area that has been positively affected by the low interest rates. A third of those surveyed said they took advantage of the rates to refinance their home.

Nearly 70 percent of those surveyed are worried they will have to pay higher federal taxes in retirement and will have a more difficult time living comfortably in retirement. Because of this, 39 percent of investors say they are more likely to seek after-tax investments.

More than 1,000 investors across the country were surveyed for this study.