Sen. John McCain (R-Ariz.) came to the floor of the Senate at 10:31 a.m. to argue that S.160, the D.C. Voting Rights Act, is unconstitutional. Thus begins formal debate on the bill itself after yesterday’s successful cloture vote. We’ll be keeping an eye on the debate all day, noting that Mary Beth Sheridan reported this morning that Majority Leader Harry Reid has now said that a vote could come today.

McCain seems pretty agitated about the bill. He just called it an “attempt to buy votes,” a “political deal.”

BTW, C-SPAN2 just put up on the Chyron that the final vote on the Senate bill “could come Thursday.”

10:51 a.m. McCain wraps up after having gone through a number of arguments, including that Utah should not be allowed to get an extra seat without being granted one by the U.S. Census. He says the way to get D.C. voting representatives in Congress is by constitutional amendment. He called the compromise with Utah “political horsetrading,” and says he has no doubt this bill is unconstitutional.

10:57 a.m. Lieberman is responding to McCain now. We’ll be seeing a lot of Lieberman, as the bill’s manager, arguing for the District today.

11:20 a.m. Now it’s our new favorite senator, Jon “All Members of Congress Represent D.C.” Kyl! I tell you, with the one-two punch of McCain and Kyl arguing against the bill so far, it’s a tough day to be an Arizona native turned loyal D.C. resident. Sigh.

11:39 a.m. Longtime voting rights proponent Patrick Leahy from Vermont has been speaking for a few minutes now. Leahy says Kyl’s argument is “no substitution for direct representation.” He’s really mocking the notion that any senator’s own constituents would be happy hearing that someone from some other state would be representing them.

11:50 a.m. OK, it looks like the Senate debate has now moved totally over to discussing a possible truth and reconciliation commission. Leahy turned to that topic and now Sen. Sheldon Whitehouse (D-R.I.) is taking up the cause. We’ll come back if debate returns to S.160 later today.

12:01 p.m. Oh wait, it looks like this was an amendment? We didn’t totally follow that, but it did pass. Lieberman made no objection to whatever the amendment was, so we’d say it wasn’t a fatal amendment.

Now Sen. John Ensign (R-Nev.) has come up, and he’s talking about D.C.’s handgun ban history. Since the Supreme Court’s Heller ruling, “the D.C. Council has continued to exact onerous and unconstitutional firearms regulations on law abiding residents,” he says. He’s attaching an amendment to S.160 tying the voting rights bill to a repeal of the 2008 D.C. gun law. This does not bode well.

Ensign has a big chart “showing” how D.C.’s murder rates went up at the same time that our gun laws became more restrictive, so he’s claiming what here, that the handgun ban only encouraged murders? Good grief, talk about bending statistics until they are meaningless. Perhaps Ensign is familiar with the crack epidemic?

12:22 p.m. Whoa. Alaska Sen. Lisa Murkowski (R) says she intends to introduce a constitutional amendment TODAY to get D.C. its voting representatives, and that she’ll work to ensure its ratification. She’ll be voting no against S.160, and her amendment will not be part of S.160. Murkowski, as you’ll recall, was one of the surprise yes votes for yesterday’s cloture vote. During her time on the floor, Murkowski noted that her state has only a slightly larger population than the District, and that she agreed that we deserve representation, but that she wants to “get it right the first time.”

Senator Tom Coburn (R-OK), another of our favorite senators, then announced he is going to introduce legislation to exempt D.C. residents from federal income taxes. Leave it to Coburn to make a mockery of the District’s status.

12:38 p.m. Jeff Sessions (R-Ala.) has now been rambling on against the bill for some time. Am now beginning to wonder how long I can continue to listen to these guys.

12:49 p.m. Maryland’s Barbara Mikulski (D) has injected a little energy into the proceedings with her booming voice. She errs a little though, in our opinion, by focusing on how Eleanor Holmes Norton is so awesome that she should have the vote. We love Eleanor, but this bill shouldn’t be about her. Sure, she’d presumably win the first special election for a real House member, but she won’t be around forever, and District residents should hope that even more exciting and qualified candidates would decide to run for such a seat down the line.

12:54 p.m. “Big Bad” John Cornyn (R-Tex.) is here. He thinks it’s a “very serious mistake” for the Senate to pass a bill that he believes is unconstitutional just because they “have the votes” to do it.

Heh. Cornyn starts keeping it real, asking his fellow senators whether they are willing to tell their constituents that their state lost out on a House member so that D.C. could have one. At least he’s honest in his appeal to his colleague’s interest in representing their state and their state alone. Cornyn’s argument pokes some pretty big holes in Kyl’s, though.

I should note, when McCain first began this debate this morning, he motioned for a “point of order” on the bill’s constitutionality. A point of order means that McCain has moved that this bill constitutes a violation of a rule of the Senate. Most of the GOP senators who have gotten up to speak since then have argued in favor of McCain’s point of order. I gather it’s a little like asking for a case to be dismissed at the beginning of any trial.

1:35 p.m. DCist is grateful to Iowa Sen. Chuck Grassley (R) for introducing an entirely unrelated bill. We will now hurry to resume your regularly scheduled DCist programming while we still can.

2:00 p.m. Sen. Robert Byrd (D-W.Va.), the oldest member of the Senate, is now on the floor. He’s long opposed the D.C. Voting Rights Act, and is calling for a constitutional amendment rather than legislation. It’s almost impossible to watch Byrd speak without giggling at his old coot style. “Where? In Congress! What’s Congress? Here!”

2:15 p.m. The senators are now voting on McCain’s point of order. It’s not totally clear to me what might happen if the point of order is upheld — would the Senate then be forced to abandon S.160 altogether? We’ll see what happens.

2:36 p.m. The point of order has failed, by a vote of 36-62. So, no need to worry about its implications.

3:03 p.m. Sen. John Thune (R-SD) has introduced an amendment that would allow individuals to carry registered, concealed firearms across state lines if they have a valid permit. He claims this amendment is relevant to this debate because of all the conversation about the difference between “states” and “D.C.”—of course, it’s just a rather naked attempt to derail the legislation by adding an unrelated amendment.

3:16 p.m. Oh boy. Jon Kyl is back, this time to offer a retrocession amendment. I can’t wait to see what Barbara Mikulski has to say about this! No serious person could ever think the current Maryland legislature would agree to retrocession.

3:29 p.m. Sen. Dick Durbin (D-Ill.) is making an impassioned speech on the floor right now about guns. He’s doing a pretty good job of making John Thune look like a crass buffoon for introducing his amendment. “Kids are getting gunned down every day, particularly in Washington, D.C.” Earlier Durbin went into some of the same issues he brought up yesterday — that members of Congress routinely like to “play mayor” for the District of Columbia in a way they would treat no other jurisdiction.

3:56 p.m. If you’re not watching C-SPAN2, you’ve missed out on Jim DeMint (R-S.C.), who introduced a fairness doctrine amendment. How is this relevant to the D.C. Voting Rights Act? “If we don’t respect the constitution on one end, why should we respect it on the other?” Good gravy.

OMG Sen. Roland Burris! Ehh, do we really want this guy coming to bat for us? Maybe!

4:18 p.m. Lieberman gave a long rebuttal to the amendment process that’s now unfolding — we missed a good chunk of it. Now Sen. Robert Bennett (R-Utah) is talking about the fairness doctrine amendment. I can’t believe we’re even discussing the fairness doctrine during this debate.

4:26 p.m. Tom Coburn is back, calling his amendment “simple.” “While we wait for this to be settled,” let’s eliminate federal income tax for the residents of the District of Columbia, he says. He suggests D.C. would see enormous growth and modernization as a result. We suggest D.C. would become the world capital of organized crime. … “By the way, this excludes all members of Congress.” HAHA, thanks for the laughs, Coburn.

4:38 p.m. Chuck Schumer is scolding his colleagues for supporting Ensign’s amendment, which would repeal the District’s current gun laws. Points out that these same colleagues tend to support state’s rights to decide these things, but not for the District.

5:47 p.m. So, the Senate is now going to vote on Coburn’s amendment. It doesn’t have a chance in hell, but OK, here we go.

6:11 p.m. Amendment to exempt D.C. residents from federal income tax fails, 7-91. Frankly, that’s closer than we thought it would be.

6:30 p.m. Lieberman has moved that the Kyl amendment be the first amendment dealt with tomorrow morning. His motion sets up a vote on Jon Kyl’s retrocession amendment for 10:30 a.m. on Thursday. In other words, no way we’re going to see a vote on the bill itself tonight.

7:28 p.m. Reid finally called today’s session to a close, reiterating when he did that Senate debate on S.160 will resume at 9:30 a.m. tomorrow, with the first hour being reserved for Jon Kyl’s retrocession amendment, followed by a vote on that amendment at 10:30 a.m. After that, the debate will likely unfold much like it did today, with various roll calls and amendment votes. We’ll be paying special attention to the fate of the Ensign amendment, which would repeal the District’s current handgun registration laws. A final vote on the bill itself could come tomorrow, or Friday at the very latest.