Hell, they'd be more likely to take World of Warcraft money, because that's a huge group of voters and doing so, if legal, wouldn't hurt anyone or be seen as very controversial. Also, they'd appear hip, young, with it, cool, groovy, hep, radical, and bodacious.
There are ways around contribution bookkeeping issues as well, such as donations to fundraisers thrown by 527 groups rather than directly to the candidate (I believe, but could be wrong, that 527s have no rules on who can contribute and have no upper limits). Your money doesn't go to the candidate, but it'll probably "buy" the same amount of money or more at the fundraiser or at least can offset money that the candidate might instead spend.
I predict that the 2020 race will have at least one pseudo-viable candidate accepting bitcoins. Mark it.
I predict that the 2020 race will have at least one artificial candidate (see the lead singer for AKB48) accepting bitcoins.