When is a good time to donate money to a candidate?

I was not going to give any money in this election but a candidate has entered the race that I can support. I doubt s/he has a chance of winning but a strong show of money early is probably a help. OTOH, if I donate too soon, I run the risk of being hit up again and again. I don’t want to make this question about specific candidates or parties – y’all can probably guess who I mean. I’m more interested in donation strategy. Also, would you give just once and say that’s it or would you dribble it out?

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