I would say, yes, C.S. Lewis was very much a Judeo-Christian--so much so that he married Joy Davidman, an "American" of jewish descent born in the Bronx. She was a radical communist and a feminist who at one time worked in Hollywood as a scriptwriter.
He obviously believed that this Edomite jewess could be "saved" by believing in "Jesus" as is demonstrated by the Judeo epitaph he wrote for her grave:
Here the whole world (stars, water, air,
And field, and forest, as they were
Reflected in a single mind)
Like cast off clothes was left behind
In ashes, yet with hopes that she,
Re-born from holy poverty,
In lenten lands, hereafter may
Resume them on her Easter Day
Source:
http://oxfordinklings.blogspot.com/2009 ... orium.html