Senator Claire McCaskill (D) last night via Twitter:

Claire McCaskill ‏@clairecmc

Hey #StandwithRand.He’s not filibustering but using Senate rules to grandstand. Frustrating for those of us who actually want to reform NSA. 10:26 PM – 22 May 2015

Yeah, he’s grandstanding. And not really accomplishing much. But he is probably helping his presidential campaign coffers.

One of the replies:

Jeff Miller ‏@J3ffMiller

@back_ttys @redsteeze @clairecmc Grandstanding? In the senate? Surely you jest.

10:36 PM – 22 May 2015

This, too.