Due primarily to the “inability of newspapers, magazines, radio and TV to prove return on advertising investment,” spending on online promotions will nearly triple to $22.8 billion by 2012 from $8 billion last year.

That spending includes contests and coupons, and represents advertising money also spent on travel and tourism.

The study is from Borrell Associates “The Big Shift” report.

A May 2008 Business Week article says that coupon Web sites are getting more traffic this year. The magazine cited March 2008 comScore data showing business was up 38% from the same time last year.

Some marketers are using other digital channels for promotions. An Online Testing eXchange study commissioned by SeeSaw Networks and the American Association of Advertising Agencies found that more than half of US mobile users would text in response to digital outdoor promotions.

Report by David Wilkening