I'm sorry but I don't see how on earth Lee, an extremely progressive democrat who opposed the Afghanistan war in 2001 of all years would get the support of the democratic establishment who would see such a move as extremely fringe like, not to mention Lee is very pro Palestinian too.
The Californian establishment (in fact, the Sacramento establishment) isn't the Washington establishment. We already know they're unlikely to support Schiff, which is seen as Pelosi's pet and has no history of working with party leaders in Sacramento. He's a creature of Washington.