There's nothing "magic" about it. One, he way more than any other candidate is looking to bring the populace into the process to directly be able to claim a mandate and a mandate which won't just disappear after election day. He has been fighting this ethics thing pretty much on his own within the Party. There are just a handful of Senators on his side which is where his ability to enlist across the aisle was crucial. Apparently you're even more naive than I am if you think this task wasn't handed to a Junior Senator by the Dem caucus without a healthy dose of skepticism anything would be accomplished. The entrenched interests on Ethics are the middle of each Party, not just the Republicans. Getting anything passed was quite an accomplishment. It's not magic, it's being better suited both by his skill and his experience for a style of politics which is more effective than direct in-your-face confrontation.
I remember the same "getting anything passed was quite an accomplishment" rhetoric from you when Obama took that universal health care bill in Illinois, talked with all the lobbyists about their concerns, and then turned it into a bill to create a study group.
The idea is supposed to be to defeat the entrenched interests, not to give them whatever they want. I know, I know, when he's President it's going to be totally different.
The fight will just begin when he's President. None of us are under any illusions about that. But the fact is that he's shown more of any ability to fight and win these battles than either of his opponents, and I'm not particularly certain which side Hillary is even on.