"The magic number of delegates for Trump to clinch the nomination on the first ballot, likely to be his best and perhaps only chance to do so, remains 1,237. But there are now whispers that the real number of delegates Trump must win by June 7, when the final contests take place, may be lower.
“The closer he gets to 1,237, even if he doesn’t get all the way there by the final primaries, the more likely he cobbles it together,” said one RNC member attending the quarterly party meetings in Florida, where sideline conversations are focused on this subject. “There are plenty of delegates that are unbound on first ballot, you’ve just got to go find them.”
When the convention opens in Cleveland in mid-July, roughly 200 delegates will arrive as free agents, unbound by the results of primaries or caucuses in their states. Trump’s campaign is confident they can win as many of them as they must in order to get to 1,237 on the first ballot."