I do think that there are fervent UUers. I am still working this out, on paper, but i suspect that, much like Judaism, UU is a "religion"primarily of practice, or praxis- if you want to get academic about it.
So in both, and there is scholarly research to support this grouping of the two together, the emphasis is on doing Right (v. believing the right thing: doctrine).
of course, Judaism is monotheistic and dogmatic in ways that would make UUers sick.
Still, UUers live by 7 principles and the first is that all beings have worth and should be respected. I feel sure that no UUer worth any salt would convert to a hateful regime.
IN the research i did after i posted, I read that UUers are practicers of a Different Religiosity. They are quite different from traditional religions. For example, UUers as a set value spiritual growth highly, but value "Salvation" so lowly that it almost qualifies as a disvalue.
not your mama's Faithful, now, huh?!
Did i mention i love this stuff?