Mitt Romney has instructed his closest advisers to explore the possibility of stopping Donald Trump at the Republican National Convention, a source close to Romney's inner circle says. The 2012 GOP nominee's advisers are examining what a fight at the convention might look like and what rules might need revising. "It sounds like the plan is to lock the convention," said the source. Romney is focused on suppressing Trump's delegate count to prevent him from accumulating the 1,237 delegates he needs to secure the nomination. But implicit in Romney's request to his team to explore the possibility of a convention fight is his willingness to step in and carry the party's banner into the fall general election as the Republican nominee. Another name these sources mentioned was House Speaker Paul Ryan, Romney's running mate in 2012.