Why is the election system rigged against Dem's and independ?

THe system is made so that independents aren't supposed to win. The electoral college was set up, to HELP republicans.

Why is this. Trump was right when he said it's rigged, but he was wrong when he said it's rigged against him. It's rigged against dem.'s and independents

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by the way, trump once ran as an independent a long time ago. He lost. To prove his point. He ran as a republican, and won the electoral college, ONCE
Why is the election system rigged against Dem's and independ?
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