Democrats are the minority and an unusually monolithic block. Even republicans at their lowest weren't standing shoulder to shoulder like this.

So yeah, even if republicans all vote for it, they'd still need 8 senators to flip, and there's another thing to consider. 2018 is a very rough senate map, now you think - well that should make them flip to avoid any fire. True, but that'd also kill any funding from the DNC for them. So either they lockstep or they can already announce retirement because the first person to primary them is getting all the money.