Point is to deny Romney 1,144 and let a floor fight at the convention decide. Romney only needs to lose about 55% of the upcoming 19 states' delegates to be in that position.
And really with Gingrich polling in the single digits, how do you think this could even be remotely possible? The only guy who could have possibly done so (Santorum with 11 states and over 3 mllion votes cast for him) has pulled out. That floor fight will not happen. The fight now is to get a real conservative as VP.