According to the New York Times Caucus Blog, the Romney campaign bused students in from colleges on the Eastern Seaboard to ensure that he had enough supporters there to enable his victory in the straw poll.
...Straw polls indicate very little. The voting pool is affected by who attends the conference — 44 percent of voters were students — and by special efforts campaigns can make to bring in supporters for the vote. In each of the last two years, Mr. Paul was the victor, but others said this was more a mark of his campaign’s organizational ability than its true support...Do I care? Not really. This is all well within the rules of the game, but let's not pretend that this is some "severely" impressive display of the strength of Mitt Romney with conservatives.
....The Romney campaign also worked aggressively behind the scenes for a strong showing, including busing students from colleges along the Eastern Seaboard to show their support....
Cross posted at Redstate