George Zimmerman is mailing hand-signed thank you cards to people who donate to his defense fund.

“Each card will be [personally] signed by George. The identity of all donors will continue to be kept strictly confidential, and the envelope of the Thank You Cards will not have any reference to Mr. Zimmerman or the O'Mara Law Group,” says a post on Zimmerman’s defense fund website.

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Zimmerman’s attorneys may be using the cards to entice more donations from the public. A posting on the GZdefensefund.com from Wednesday says Zimmerman needs more donations.

Since the creation of GZdefensefund.com on May 3, Zimmerman has raised more than $140,000 but the posting claims the balance of Zimmerman’s defense fund is, “at its lowest, and new funds must be raised to support George’s living expenses and legal costs through the end of the self-defense immunity hearing and/or trial.”

According to the website, a new defense fund manager will handle donations and once the fund is “under new management,” Zimmerman will pick up his “fund-raising efforts” to include "an updated GZDefenseFund.com website, a disclosure of how funds have been spent and provide regular updates of how money will be spent in the future."

The post also criticizes the publicists and attorneys who have profited from Martin’s death, “[G]eorge Zimmerman was the victim of a coordinated public relations attack designed to assert that George acted with racial bias, a public relations attack that was perpetrated with the intent to prejudice the media and the citizens of this country with unfounded misinformation about George, and with the purpose of profiting from a tragedy,” says a post on Zimmerman’s defense website.

Zimmerman has pleaded not guilty to a second-degree murder charge for shooting 17-year-old Trayvon Martin on February 26. Martin was returning from a convenience store and was unarmed. Zimmerman told police he shot the teen in self-defense.