There are many reasons for this that I don’t have time to cover in a short essay, but one of them is clearly logistics. It is incredibly difficult and expensive to run nationally as a third party or independent candidate. Some important state deadlines have already passed and some states have extremely difficult barriers to overcome to get on the ballot as an independent or third party candidate. The crucial state of Texas is an example of both of these problems. You almost have to use paid professional signature collectors in some states and at a couple of dollars a signature that’s not cheap. The #NeverTrump third party advocates have also indicated that they are prepared to mount expensive legal challenges in states were deadlines have already passed, and there is no guarantee that these challenges would even succeed.
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