In a letter to the editor in today's WSJ, Jeff McCormack proposes a strategic bargain among the non-Trump candidates.

Update (3/11):  The NYT reports:

A top aide to Senator Marco Rubio on Friday urged his supporters in Ohio to back Gov. John Kasich in that state's primary on Tuesday, giving fresh momentum to efforts to stop Donald J. Trump a day after a debate in which his rivals declined to take a swing at the leading Republican presidential candidate.

Alex Conant, Mr. Rubio's spokesman, made the comments in an interview with CNN. He said that he hoped supporters of Mr. Kasich and of Senator Ted Cruz would support Mr. Rubio in his home state primary in Florida, and that he would suggest Mr. Rubio's backers in Ohio do the same by supporting Mr. Kasich there.