The current thinking on possible frames falls into four distinct but overlapping stratagems:

Trump can’t be trusted because he is an egomaniac with a bad character (his business dealings; his bankruptcies; his two divorces; his insulting statements about women; his casinos; his compulsion to name things after himself; his hazy answers about his own faith; and his aggressive use of eminent domain).

Trump is a liberal and unprincipled (past support for single payer, the Clintons, House Democratic Leader Nancy Pelosi, and abortion).

Trump is not close to being fit to be a serious president or commander-in-chief (his recent answers on foreign policy; his lack of specifics on almost everything).

Trump is a politician, not a businessman/outsider (his long-time retention of Beltway lobbyists; his self-serving campaign contributions; his courtship of local, state, and national officeholders).

All of these frames have some potential, according to those who wish to end Trump’s domination of the Republican nomination process. But picking one (or two), and driving the message to success is as difficult as it is vital to his foes. There is by no means consensus on which of these frames will work or how to flesh them out. One school of thought, according to my reporting, is to go with an amalgamation of “deals and females,” on the theory that those are Trump’s twin vices and the opposition could use those issues to at least pry away some parts of his current coalition and bring his poll numbers down closer to the pack. The hope is that should Trump’s numbers go lower, he will get rattled, his aura of invincibility will dissipate, and his mojo will be disrupted.