About eight per cent of US readers use an e-reader. But a Harris Interactive poll released last month showed that about 12 per cent of Americans, or one in eight, said they are likely to get one in the next six months.
"With e-reader sales expected to continue to climb and as more devices now become available, it is inevitable that reading habits of Americans will change," Harris said in a statement.
The poll of 2,775 US adults, showed that e-reader owners were far likelier to buy books than other Americans.
About one fifth of e-reader users bought 21 or more books in the past year, far about the 12 per cent of Americans overall who shopped at the same rate. E-books now make up about three per cent of book sales but analysts expect that to quadruple by 2015.
According to consulting firm Forrester Research, Amazon.com's Kindle, launched in 2007, has already sold about 5 million devices while Barnes & Noble Inc, the largest U.S. bookstore chain, has sold about 1 million "Nook" e-readers since its launch last year.
Other leading devices include Sony's Reader and Apple Inc's iPad computer tablet, which has e-reader capabilities.
Amazon, Barnes & Noble, Apple and Borders Group Inc, which does not make its own e-reader but sells the devices, are waging an all-out war for the growing e-books market, with devices a key part of their strategy.
For all their growing popularity, e-readers seem destined to remain popular mostly among the most avid bibliophiles. About three in five Americans questioned in the poll said they were not at all likely to buy an e-reader in the coming months.