Americans signed up for broadband cable and DSL in record numbers in the first quarter, according to a study released Tuesday by the Leichtman Research Group.

Although DSL providers'' 1.38 million new subscribers represented 54 percent of net broadband additions for the quarter, cable broadband with its total of 21.1 million broadband subscribers retained its comfortable overall lead over DSL, which has a total of 14.7 million subscribers. A total of 1.19 million new broadband subscribers signed up for cable in the first quarter.

"Deeply discounted introductory offers again drove a surge in broadband adoption in the first quarter of 2005," said Bruce Leichtman, president of the market research firm, in a statement. "In the past six months, nearly five million subscribers have added broadband service in the U.S."

Comcast leads cable broadband subscribers with a total of 7.4 million subscribers including 414,000 new subscribers who signed up in the first quarter. SBC Communications leads the DSL category, signing up 504,000 new subscribers to bring its total up to the 5.6 million mark.

The Leichtman Group covers the 20 largest cable and DSL providers, a figure that represents about 95 percent of the total broadband audience.