If we're assuming the kind of time/resources that it requires to affect political change, then no, you don't really have to abide by anything.
You can either opt out, or you can wade into a corrupt system and start finally enjoying your ability to join in on all the corruption. In the 2nd case, what's the plan moving forward for an ethical actor really? Using money to bribe politicians into stop accepting bribes? Should we bribe citizens to stop electing politicians that accept bribes? If you don't want money involved in politics then I don't know how you start to fix that with money.
You can either opt out, or you can wade into a corrupt system and start finally enjoying your ability to join in on all the corruption. In the 2nd case, what's the plan moving forward for an ethical actor really? Using money to bribe politicians into stop accepting bribes? Should we bribe citizens to stop electing politicians that accept bribes? If you don't want money involved in politics then I don't know how you start to fix that with money.