As of January 15th, the American Red Cross raised approximately $249 million for those affected by Superstorm Sandy. At the end of 2012, $110 million had been distributed to the impacted areas. The top Sandy fundraiser followed a pattern among many groups raising cash for Sandy victims; according to charity watchdog groups, less than half the money collected has been spent.

At SmartResponse.org, dozens of charities reported more than $445 million raised in total. The burn rate, or how much has been distributed, sits at 40 percent.

"Certainly, many groups have slowed their operations in many places," said Ben Smilowitz, executive director of the Disaster Accountability Project. "Some of that's warranted, and some of that's probably inexcusable."

As of 12/31/12, the American Red Cross spent $110 million of the Sandy relief money it raised. (Spencer Platt, Getty Images)

Smilowitz singled out the American Red Cross for a lack of transparency. Given the group's mission to provide urgent relief, he said it makes sense to question the pace at which the group is dispersing its funds.

"Those responding to Sandy also have a major obligation to be transparent about what they do," Smilowitz said.

In a conversation with Townsquare Media, the American Red Cross said they have plans to distribute another $60 million during the second phase of assistance.

Overall, Smilowitz said some organizations have been heroic with their Sandy-related offerings; others have been underperforming. A number of groups, including the Robin Hood Foundation, have been slow to distribute funds because they provide local grants rather than direct help. The process can take time as the foundation ensures they are giving to reputable groups.

A major problem arises, according to Smilowitz, when the bulk of the money raised comes from "outside groups."

"Oftentimes, decisions for what needs to be delivered are made by outsiders and not by those directly impacted," said Smilowitz.

He advised donors to do some research before giving to charities after a disaster. He said one's donation could make more of a difference if it's given to an organization based in an affected area.