That's nothing... They actually do it much easier and in your face!
Special luncheon, fundraiser, whatever with Guest Speaker "put name here"...
Guest list undisclosed (always) but as an example usually $10,000 per seat, with the guest speaker getting tens of thousands for showing up for a 10-20min ooohaaa!
Book deals are peanuts, and is only to just keep you name in the news/spotlight.
Here Pence has been rumored to be contemplating a 24' run and this is what's called dipping the toe in the water. Of he draws a lot of interest, then he'll get backers...
The other way to major financing is those cute little Charities/Funds they set up. Like Clinton's "Pay to Play"... Funny how this isn't even a glimmer in the news any more, like Biden's kid!
How times have changed because during the Clinton administration all the left did was complain about how the news media was out to get them! Now THAT would be a worthy "study" to examine exactly how they turned those tables...
I have long thought that book deals, especially to the clintons and obamas were nothing more than outright bribes. They certainly don't make any economic sense. The advances given outweigh any profits from the actual sales. So how can they be justified? One would think an enterprising reporter might follow the money trail to understand this story better. But because it would potentially expose wrongdoing by democrats of course no one will follow up.