Any contributions go to a common pot allotted by a caucus vote system. I don't think a crackpot going up for election should get the same (monetary/election) support as people who actually have tenable platforms, so I would not advocate for equal redistribution.
One person's crackpot is another's advocate. The amount of money going to fringe candidates would be minimal at best, while those that are serious contenders would get a well-deserved bit of assistance.
You can fine-tune this a bit, like have minimum vote requirements (e.g. 5% of the votes) in order to be part of the program, but the basic idea helps frame things better.
If you look at how most elections go, the extreme fringe candidates get at most hundreds of votes, it's inconsequential in the scheme of things.
This was roughly how it worked at the federal level in Canada until the Conservative party cancelled it in 2015. If you got at least 2% of the vote you got a "per-vote subsidy" of $1.75 per vote.
The reason the Conservative party killed the program was because it hurt the other parties more than it hurt them. As they were always better at raising money, anything that cut funding to the other parties was seen as a big win for them: Like the Republicans they are very self-interested.
There are multiple parties active in the Canadian system, some only getting 5-10% of the votes, which means they're at even more of a disadvantage than before.
