BTIG (login required) conducted an informal survey (via All Things D) of 250 Verizon and AT&T stores. Through their research, they found that the iPhone is the top-selling handset with both carriers. In the five months of availability for the Verizon iPhone, 51 percent of Verizon stores say that the iPhone 4 is their top seller. 38 percent of the stores say that the iPhone's sales are even with Android phones, and they usually note that it's the 4G Samsung Droid Charge or HTC's Thunderbolt.
AT&T, which has had the iPhone since its launch, is much more closely associated with the handset. 65 percent of AT&T stores say that the device is their best seller. 38 percent of AT&T stores say that Android handsets sell better.
They combined the data to see that overall 58 percent of the stores called the iPhone their best seller while 20 said it was equal in sales to Android.