DALLAS — The love-hate relationship between hotel operators and increasingly popular online travel sites took a turn this month with the launch of a Dallas-based search engine called Roomkey.com.

Founded by six major hotel chains, including Hilton Worldwide, Hyatt Hotels and Wyndham Hotel Group, the site channels consumers to the chains’ own websites to book rooms, bypassing third parties such as Priceline.com and Travelocity.com.

The launch is seen by some industry insiders as an attempt to recapture revenue lost to the online travel giants.

“This is going to compete directly with the Expedias and Hotels.com,” said Tom O’Rourke, president and chief executive of O’Rourke Hospitality Marketing. “Let’s say I’m Bill Marriott (of Marriott International Inc.). I can take that money back, put it into my property, service my guests better, and it’s a much better business model for me.”

Of the estimated $33.8 billion in hotel rooms booked online in 2011, about 55 percent, or $18.6 billion, came directly through hotels’ own websites, according to Carroll Rheem, director of research at PhoCusWright Inc., a research firm. About 45 percent, or $15.2 billion, was booked through online travel agents — up from only $2 billion as recently as 2001, Rheem said.

As the popularity of online sites has grown, so has the cut paid to the online travel agencies. That’s been a growing source of angst for hoteliers, who see razor-thin margins on some rooms sold through online sites.