A rash assumption on your part to assume Mitt would actually have a chance of getting 40% of the general election vote.
So here's the likely scenario should he get the nod: 50-60% of the GOP voters who were previously against the notion of a Romney presidency would go ahead & vote for Mitt. 40-50% won't.
Those who voted for Mitt would then have on their conscious the precedent that they voted for a RINO. And once you have on your track record that you voted for a RINO, you've already caved & compromised.
Your rash assumption that lots of people share your biases and won’t vote for the smart, articulate and accomplished business leader and former Governor is as warped as your dislike for Mitt. Let’s have the nomination first before you make rash assumptions about how much he can get in the general election.