Here's one of those 2020 GOP success stories - Iowa, where the GOP picked up two seats from the Dems.
Representative vote totals:
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GOP - 859,418
Dem - 762,271
Presidential vote totals:
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GOP - 879,672
Dem - 759,061
This indicates that not only did virtually all GOP down-ticket voters also vote for Trump, but a lot of Democrat down-ticket voters voted for Trump as well. The big difference in Iowa of course is that there wasn't massive election law violations and voter fraud like we saw in Pennsylvania, Georgia, Michigan, etc. This is representative of the overall election breakdown across the country in States where fraud didn't occur.