rich people are not againt poor people having insurance they just don't want to pay for it with increased taxes.
There is a problem with your unstated premise, that the money is theirs, to begin with.
I am not talking about Earned wages (money paid in exchange for work) here, I am talking unearned wages (money from profits including dividends and investments).
One could easily argue that profit should belong to the people since it takes all of us to do the work necessary in order to generate profits. No single person is able to bring in large profits without work from other people. Those profits represent an underpaid wage to those who have performed the work.
The question now comes, if those profits are generated by all of us, why is it so unreasonable to ask that a portion of those profits go towards making sure that the same people who generated them have healthcare?
Why is it that those who hoard large amounts of unearned wages get to decide if the people who produce them can afford to see a doctor?
Imagine being at work and having an important meeting with a potential client who could make your company’s profits double. The client shows up, and the meeting gets off to an awkward start. After a few minutes, you start to wonder what is going on. A green shimmer washes over the client, revealing that he is actually Loki. He has been wanting to meet you, but you’re always at work, so this is the only way he could get time with you. He has a project in mind, but it has nothing to do with your day job. (Interpret that any way you like!)