He talked throughout the night and is still going as of 10:00 AM:

WASHINGTON — Condemned from all sides, Sen. Ted Cruz launched a talkathon Tuesday intended to cripple Obamacare but aimed — inconveniently — at a bill that would deliver exactly what he asked for.

Cruz came to the Senate floor destined to lose, armed with a thick three-ring binder of talking points, black athletic shoes, and a willingness to shrug off the rolled eyes of colleagues who view his tactics as grandstanding.

“I intend to speak in support of defunding Obamacare until I am no longer able to stand,” Cruz declared to a near-empty Senate chamber at 2:41 p.m.

It was more theater than filibuster, though Cruz used that term to describe his effort. Senate Democrats had already scheduled a Wednesday morning vote clearing the way to begin debate on a House budget bill.

Even if Cruz’s voice, feet and bladder could hold out that long, he would have lost control of the floor at that point no matter what.

The marathon was sure to please tea partiers itching for confrontation. It cemented Cruz’s credentials as a newcomer willing to take extraordinary steps, even in a quixotic fight. But most of his GOP colleagues refused to follow him into a fight they feared could lead to a government shutdown for which voters would blame their side.

Sigh.  When will grown-ups return to Congress?

Love C-Span's caption here:

UPDATE: He ends at Noon EST.

Supposed to be on Rush at 1 pm.  Ah, I see.