For example, there are a lot of people here who think Randall Terry is a conservative, who revere him even. Of course, that doesn't make it so.
It depends who those "other people" are.
In Russell's case, if they're people who are themselves passionate about atheism, have studied it seriously and approach its promotion in a similar manner to the way a Christian evangelist tries to spread his religion, then yes that's exactly what it means.
When your writings about religion appeal to atheists-and lots of them- that actually means something.
Communists like what Marx wrote. Atheists like what Russell wrote.
What's difficult about that?