People who go online on sites like Lemmy to discuss politics are usually strongly in favor of one party over the other. However, not everyone who votes in elections is like that. There are many moderate or swing voters. Presidential elections in particular are decided by a few key swing states. There is also an expectation that the Congress and the Courts could be a check on each other and on the President, so sometimes people vote for a candidate that they don't fully agree with. Debates aren't always about which candidate or party has a more agreeable stance on the issues, but rather which issues are the most important.
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