“The cost of a presidential campaign nationally is about a 1/2 a Billion dollars... we all know the establishment, at least large swaths of it, are against you and will do whatever they can to undercut you, so if they decide to shut off the tap, are you, personally willing to spend out of your own pocket 1/2 a Billion to run a good race in the General?
That’s the one question that tells you whether the establishment will be able to stop him, if Trump is not willing to completely self support irrespective of the party structure, then he has a problem. If he is seriously committed to self funding, truly self funding, because the bombastic keep the press eye on me by being outrageous won’t get you though a general.”
That won’t be a problem. Just look at how much money Ron Paul raised from grassroots donations when he ran in 2008 and 2012. Trump can reach many times the number of people Ron reached.
Obama and Romney campaigns each spent over a billion dollars in 2012.
A single nationwide primary would likely cost successful campaigns an equal amount.