Yes, please do. 33 percent of Democrat-identified uncommitted voters demand it.

Since your historic victory in the primary, there have been troubling signs that you are moving away from the core commitments shared by many who have supported your campaign, toward a more cautious and centrist stance–including, most notably, your vote for the FISA legislation granting telecom companies immunity from prosecution for illegal wiretapping, which angered and dismayed so many of your supporters.

We recognize that compromise is necessary in any democracy. We understand that the pressures brought to bear on those seeking the highest office are intense. But retreating from the stands that have been the signature of your campaign will weaken the movement whose vigorous backing you need in order to win and then deliver the change you have promised…

In other areas–such as the use of residual forces and mercenary troops in Iraq, the escalation of the US military presence in Afghanistan, the resolution of the Israel-Palestine conflict, and the death penalty–your stated positions have consistently varied from the positions held by many of us, the “friends on the left” you addressed in recent remarks. If you win in November, we will work to support your stands when we agree with you and to challenge them when we don’t. We look forward to an ongoing and constructive dialogue with you when you are elected President.

I wouldn’t hold my breath waiting for him to denounce “mercenaries,” but never mind that. I’m intrigued by the fact that sending more troops to Afghanistan is now a sufficiently tenable position among the left (at least the HuffPo-reading left) that the Nation would dare inject it into a critique of Obama meant for wide publication. Gallup had some new information about that today, in fact: 56 percent of Democrats support redeploying some troops from Iraq to Afghanistan to bolster the effort there (which is also Obama’s position), but make the question more vague — do you support more troops for Afghanistan? — and the numbers shift to 50/47 against. That’s in line with that tantalizing bit of data from the WaPo poll a few weeks ago claiming (without giving actual numbers) that “majorities” of Democrats now think the war there wasn’t worth fighting and isn’t linked to the eventual defeat of terrorism. I keep waiting for the GOP to zero in on this, although maybe it’s a case of the party’s interests and the right-wing blogosphere’s interests not being aligned. After five years of nutroots shrieking about chickenhawks and fighting the “real war,” it’s darkly amusing for us to watch the left’s support dwindle just as the prospect of escalation finally looms; but for the Republican leadership, pointing it out only gives Obama an opportunity to break with his own side on the issue and prove to those same uncommitted voters what a sensible centrist, er, maverick he is. In which case, the less said, the better.

Be sure to follow the link for an impressive list of signatories that includes not only the guy who got tackled at a George Allen campaign event a few years ago but also Phil Donahue.