Many U.S. car dealers are anxiously awaiting payment from the government through the popular "Cash for Clunkers" program, and are starting to complain that the delay is causing a cash crunch. There are dealers that still have not been paid for clunkers that were turned in three weeks ago, when the program began, the Associated Press reports. A survey in Virginia this week found that only 2.8 percent of car dealerships had been paid. The likely culprit for the delay is the unexpected success of the program. The National Highway Traffic Safety Administration, which is in charge of it, said that the requests for rebates that have been filed amount to $1.5 billion; half of the total money that is available. One car dealer told the AP that dealerships may stop participating in the program if the government doesn't start holding up its end of the bargain.