I've been involved in politics in one way or another for a long time. I've never heard anyone ask people who do not have the spare change to make a financial contribution.
Taking care of your and your family's basic needs always comes first. Always.
@lolgop asked for one person. That absolutely should be interpreted as one person who can afford to contribute.
The same goes for "blanket" asks. No one should ever feel bad about not being able to chip in $ or volunteer if you can't.