Plan?
Best case scenarios either he doesn't get the votes because of public backlash or they can delay the vote until after the midterms and are hoping they can secure enough Nays to deny him.
I think, realistically, they are using it to give Republicans a bloody nose and maybe gain more seats in the midterms when the Republicans jam this vote through. RvW case and a potential Trump trial aren't being brought up to convince Republicans to vote Nay on Kavanaugh. At any rate, I'm pretty sure they expect the Republicans to push Kavanaugh through, its whether their other plans work out or not...