Why don’t party platforms usually help presidential candidates but can hurt their chances?

Answer 1

Name 6 people who actually have a clue what either party's official platform is. The fact that you can't is why they usually don't help. On the other hand, the candidates opponent can 'cherry pick' potentially harmful items from the platform to point out as a means of attacking the candidate.

Answer 2

Candidates usually rely on party platforms but could be in conflict with their personal views which might be disadvantages for their chance to be elected.

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