Voting 3rd party or not voting at all helps the person you want the least to be in office.
The issue is the 2 party system that is designed this way. Change the system if you want more choices (ideally by pressuring your party to do it while they are in power)
Edit: to be clear 2 parties is a mathematical certainty under first past the post voting. There are countless other voting systems that don’t suffer from the spoiler effect.
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