Sooner we move to gov't funded only campaigns, the sooner corruption in DC will come to an end.

Trump account? Democratic account? Split between two? Split among 50 states? The federal government isn’t involved in election so doubt there. I used to mark it but then haven’t in a decade because nobody seems to know where that money goes.

but IIRC there is something called "matching funds" from the gov't to official campaigns.
Have not kept up with details, sorry.

Of the taxes you pay in the government can basically do with it what it pleases. By checking that box it allocates $3 to the Presidential election fund. One common misnomer is that it reduces your refund, it does not.