Many small businesses are hoping to buoy weak holiday sales this year with aggressive marketing campaigns, according to Constant Contact.

Seventy-six percent of more than 2,000 retailers recently surveyed said they're planning more holiday promotions and other last-minute deals this season, up from 62 percent in a similar survey in 2007, the Massachusetts-based marketing firm reported. Most also said they'll launch holiday marketing campaigns earlier this year.

Only 33 percent of respondents said they're anticipating strong holiday sales this year, down from 63 percent last year, the survey found.

"There's no question the economy is a cause for concern, especially for U.S. small businesses that rely heavily on holiday sales," Constant Contact CEO Gail Goodman said in a statement. "Small businesses recognize the value of focusing their marketing efforts to enhance communication with their loyal customers, as well as to attract new business," she said.

Most respondents cited e-mail marketing as a top strategy, followed by direct mail and advertising.

"E-mail marketing and online surveys are catalysts to the success of small businesses in any economic environment, but they can make the critical difference in trying times," Goodman said.