Bob Herbert has been paying attention:

Questions for the Clintons – New York Times

… The mayor’s thoughtful, respectful, generous assessment of the field echoed the tone that had prevailed until recently in the Democratic primary campaign. That welcome tone has been lost, undermined by a deliberate injection of ugliness, and it would be very difficult to make the case that the Clintons have not been primarily to blame.Bill Clinton, in his over-the-top advocacy of his wife’s candidacy, has at times sounded like a man who’s gone off his medication. And some of the Clinton surrogates have been flat-out reprehensible.

Andrew Young, for instance.

This week, while making the remarkable accusation that the Obama camp was responsible for raising the race issue, Mr. Clinton mentioned Andrew Young as someone who would bear that out. It was an extremely unfortunate reference.

Here’s what Mr. Young, who is black and a former ambassador to the United Nations, had to say last month in an interview posted online: “Bill is every bit as black as Barack. He’s probably gone with more black women than Barack.”

He then went on to make disgusting comments about the way that Bill and Hillary Clinton defended themselves years ago against the fallout from the former president’s womanizing. That’s coming from the Clinton camp!

And then there was Bob Kerrey, the former senator and another Clinton supporter, who slimed up the campaign with the following comments:

“It’s probably not something that appeals to him, but I like the fact that his name is Barack Hussein Obama, and that his father was a Muslim and that his paternal grandmother is a Muslim. There’s a billion people on the planet that are Muslims, and I think that experience is a big deal.”

Pressing the point, Mr. Kerrey told CNN’s John King: “I’ve watched the blogs try to say that you can’t trust him because he spent a little bit of time in a secular madrassa. I feel quite the opposite.”

Get it?

Let’s start with the fact that Mr. Obama never attended a madrassa, and that there is no such thing as a secular madrassa. A madrassa is a religious school. Beyond that, the idea is to not-so-slyly feed the current frenzy, on the Internet and elsewhere, that Senator Obama is a Muslim, and thus potentially (in the eyes of many voters) an enemy of the United States.

Mr. Obama is not a Muslim. He’s a Christian. And if he were a Muslim, it would not be a legitimate reason for attacking his candidacy.

The Clinton camp knows what it’s doing, and its slimy maneuvers have been working. Bob Kerrey apologized and Andrew Young said at the time of his comment that he was just fooling around. But the damage to Senator Obama has been real, and so have the benefits to Senator Clinton of these and other lowlife tactics.

… and anyone who thinks it’s not a deliberate campaign is nuts.