A majority of Americans would like to give more to charity, but most feel they do not have enough money, according to a study by Fidelity Charitable released Thursday.

Sixty-four percent of the 3,200 donors who participated in the study, “Overcoming Barriers to Giving,” say they want to give more than they do, but even more (72 percent) are concerned about their own finances, says Fidelity Charitable, a donor-advised fund.

The second-biggest reason people hesitate to increase their giving is their fear the donations will not have the impact they want, according to 62 percent of the respondents.

“While donors have other questions and concerns, bridging the gap about finances and charity effectiveness has the greatest potential to help donors realize their giving goals, the study says.

Nearly half of donors also say a larger tax benefit would influence them to give more.

Fidelity recommends advisors help their clients give more by encouraging them to automate their giving and by educating them about assets other than cash that can be given to charities, such as appreciated stocks and real estate. Donors should also make giving a part of their household budget.

Research tools such as Charity Navigator and GuideStar are available to help clients learn more about giving. And advisors should encourage clients to check out nonprofits personally if they can, Fidelity says.