The number of people using broadband mobile Internet connections jumped to 2.16 million in the final three months of 2007 as compared to 854,000 in the same period a year earlier, according to comScore.
"Though mobile broadband access is currently used by about one percent of the total US Internet population, it is poised for significant growth over the next few years," said comScore senior vice president Serge Matta.
"As consumers increasingly demand and depend on portable Internet access, the demand for mobile broadband should continue to increase."
Mobile broadband relies on cellular telephone networks. Users pay subscriptions for access and connections are made wirelessly through "smart phones" or with cards or hardware designed for laptop computers.
The comScore study focused on direct mobile broadband connections and did not include use of wireless "hotspots" such as those common at cafes, airports or hotels.
Telecom companies Verizon and Sprint commanded most of the US broadband market in 2007, but rival AT&T has announced plans to increase its coverage in that market, according to comScore.
The comScore study indicates more than half the US mobile broadband use is done from work computers and that more than 75 percent of the users claim household incomes of more than 50,000 dollars annually.