THE campaign for our votes began in a fairly civil fashion, the sides lining up to debate the issues like two men having a friendly pub row.

Even the publicity stunts were jovial. The No lobby paraded an inflatable white elephant. The Yes supporters sent out an 8ft rat.

But as the deadline of November 4 looms, every day that passes sees both sides growing increasingly shrill and belligerent.

Yesterday, for example, was the lowest day so far in terms of honest debate.

It opened with No rebuffing the Yes claim that they were southerners by "exposing" Yes' southern links. The No group even revealed that the person inside Yes' rat costume was a public schoolboy from £15,000-a-year Westminster School, in London.

Yes immediately responded by saying they had no southern links they were not proud of, and that their man inside the rat costume was, in fact, a student at Durham University.

The issue was an echo of the recent Hartlepool Parliamentary by-election, in which candidates produced their birth certificates to prove they were local.

To hammer it all home, Yes sent Ray Mallon up from the south of the region, who waved away a megaphone, but shouted very loudly at the No campaign's office.

No accused Mr Mallon of being hysterical, and the unofficial No campaign piped up from the sidelines and challenged Mr Mallon to a verbal duel in Sunderland.

Andrew MacMullen, a lecturer in politics at Durham University, said: "Campaigns do develop tunnel vision.

"It looks from the outside like a private argument that is not really relevant. Most of this goes over the heads, or past the ears, of the ordinary voter, who cannot see the point in it."

The mechanics of such an upheaval in government -such as what powers an assembly would have and how much it would cost -have been sidelined in favour of backbiting and personal attacks.

Mr MacMullen said: "The problem for the supporters of an assembly is that its powers and functions are not easy to explain.

"It is a difficult thing to get across and this gives ammunition to the No vote.

"The Yes campaign started off with a rather generalised, soft-focus campaign, with pretty pictures and celebrities, then realised this was not going to be enough.

"They have hardened it up. They needed to get a few more political street-fighters out."

That's why Yes have taken to the streets this week with political bruisers such as Ken Livingstone, John Prescott and Gordon Brown, who sniped away at what they see as a southern-orchestrated Tory No campaign. But their words were small-arms fire compared to the Howitzer Yes wheeled out yesterday.

The man formerly known as Robocop marched through Durham City centre to the headquarters of North-East Says No and bellowed enthusiastically at those inside.

It was the political equivalent of asking them all outside for a fight.

Mr MacMullen said: "Ray Mallon is prepared to be pretty tough and fairly rude, and this certainly indicates a change in direction. At the start, the No campaign took the Yes people by surprise.

"They came out hard-hitting and, in a way, more professional.

"Since then, there has been an effective counter-attack, but it has taken its time to get going.

"The worry from the Yes campaign's point of view is maybe they have left it too late. We will have to wait and see."

Hopefully, Ray Mallon's attack will be the last salvo in a referendum campaign that has taken a sour turn.

At present, the rational debate has gone. In its place are two faces, flushed red and screaming at each other. One is yelling "Yes" and the other "No". Put together, all they produce is white noise drowning out the real argument.