Reality television, dominant on the tube, is making its most dramatic foray onto the Web. On Tuesday, Simon Fuller, the British creator of the popular singing competition TV show called “American Idol,” will debut “If I Can Dream” on Hulu.com. The show follows five young people - three actors, a musician and a model - hoping to succeed in Hollywood. The show debuts as they move into a Hollywood Hills house. Their lives will be followed not just by the weekly program, but by a live stream on ificandream.com. The hype has been “Idol”-sized. The show promises “24/7 real-time interactive access.” Fans can connect to the contestants via social networking sites. On Monday, media were even invited for a “sneak preview” of the house.