Get elected to the state legislature or the party state committee, depending on the state. Either way will require the lucky candidate to spend either a few hundred hours a year or some tens of thousands of dollars a year for 3 to 10 years to get the job done, while working with like minded people with the same goals all around the state. This is called retail politics, and is basically the same as it has been since the Roman Republic. It involves a lot of energy and a genuine willingness to meet people, or a small fortune to succeed.
That’s discouraging to say the least. I doubt anyone here has that amount or time or money. I know I don’t.