Apple’s new iPhone 6 and 6 Plus are the top-selling devices at the four major wireless carriers and other outlets in the United States, according to new analysis from Canaccord Genuity.

The 5.5-inch phone, designed to compete with big-screen phones such as the Samsung Galaxy, is showing particular strength for Apple, analysts wrote in a recent client memo.

“The larger-screen iPhones could result in very strong first half/fiscal 2015 high-end smartphone market share gains for Apple,” wrote T. Michael Walkley and Siddhartha Sinha on Oct.13.

Their studies point to “a greater mix of Android smartphone consumers switching to the iPhone 6 smartphones than the iPhone 5 series, primarily due to Apple entering the larger screen smartphone market segment.”

“In fact,” they added, “we have lowered our Android smartphone estimates due to our surveys indicating strong iPhone share gains.”

The Android manufacturer feeling the most pain? Samsung, according to Walkley and Sinha.

“We have lowered our Android smartphone estimates, and particularly those for Samsung, [which] is most impacted by Apple’s high-end smartphone share gains,” they wrote.

There only seems to be one problem for Apple: there’s more demand for the iPhone 6/6 Plus than there is supply. Canaccord Genuity surveys show the iPhone 6 Plus was out of stock at AT&T, Sprint, T-Mobile and Verizon, with wait times hovering at between two and three weeks.

“We believe demand could exceed Apple’s ability to supply the iPhone 6 models through year-end,” said Walkley and Sinha.

Even so, the two analysts are predicting that Apple will ship 63 million new iPhones in the first fiscal quarter of 2015 and 53.6 million in the second fiscal quarter. On top of that, Apple is slated to release the 6 and 6 Plus in China, the most populous country in the world and one with a burgeoning middle class, at the end of this week.