Both.
The article discusses the observed trend that when the polls ask both the Trump-Harris question AND the full field question, President Trump's result goes down more than Harris' on the full-field result.
You used the phrase "RFK's belief that he would get more Trump voters than Kamala voters." I'm showing actual polling data that suggests that it is more than a "belief," it is an observable trend from multiple polls over several weeks.
Here is the most recent post of mine from 8/4/24 analyzing 28 polls from 7/25 to 8/4 showing the impact of Kennedy on the polling results. I'm sure I can add several more polls to that list from the last 10 days.
For grins, here is the first post of mine from 7/31/24 with a much smaller number of polls that began to show the trend. I reposted the 7/31/24 analysis to another thread later that day. Ironically, you were the second-to-last poster to that thread. 😉
-PJ
Remember, the early polls showing Kasich winning in 2016 turned out to be worthless because voters thought of him as a "generic republican." I.e. Kamala is still a "generic Dem" and they are trying to hide her as long as possible.
And I am still not sure how many competitive states' ballots will keep RFK.