TORY MPs have been entertaining themselves with an e-mail sent out by the Sergeant at Arms, Michael Cummins, to highlight a new free postal service to Government departments.

It said: "There are up to seven collections a day between Parliament and Government Departments via the Inter Despatch Service (IDS).

"Members and their staff are encouraged to make use of this service when writing to Government Departments.

"Letters should be placed in the internal mail service addressed to the appropriate Government Department with "IDS" printed clearly in the top left-hand corner of the envelope."

The gallows humour is that the letters marked IDS could mistakenly make their way to Sir Michael Spicer, chairman of the backbench 1922 committee. Under Tory rules it would only take 25 to spark a leadership contest and at least the waiting would be over.

For the moment the real IDS stumbles on, but it's beginning to look like an act of cruelty. In boxing, the towel is thrown into the ring. In horse racing, the jockey drops his whip or, in sad circumstances, the screens come out and a gunshot is heard.

IDS is sent to the chamber of the Commons to face an emboldened Tony Blair and hundreds of cheering Labour MPs.

(They take great delight in saying they are cheering because IDS is so useless they want him to stay. This may just be an interesting piece of spin to add to Tory woes, but the effect on the leader must be daunting either way.)

On his own frontbench they smile, but he must have no idea whether this is out of affection or pity.

On Wednesday he tried his best, arguing the average pensioner couple now needs savings worth £180,000 to avoid means testing for benefits.

These people were being forced to "go cap in hand" to the Government just to make ends meet, he protested during a series of angry exchanges.

But the dreaded frog in his throat returned. He denies it is nerves, saying it is caused by over-use of his voice.

That may have been true on this occasion because he certainly used his voice a lot touring television studios to deny any wrong-doing in the predictably named "Betsygate" scandal on Tuesday night.

However it only served to give the impression of a faltering man, waiting to be dealt the fatal blow. It is anyone's guess whether that will come from the investigation into claims he improperly paid his wife Betsy - or BDS, as she is known at Central Office - for constituency office work.

IDS and his accuser, the investigative journalist Michael Crick, insist they have strong cases. But, perhaps unfairly, the outcome may be irrelevant. His strongest selling point had always been his integrity and the public - rightly or wrongly - still believe in the adage "no smoke without fire".

Certainly the bookmakers think he is done for. Ladbrokes suspended betting he will go by the end of the year after a deluge of bets slashed the price from 12/1 to 3/1 in just 24 hours.

York-born David Davis was made the favourite to take over at 11/4. Next is former chancellor Kenneth Clarke at 3/1, along with party chairman Theresa May.

Ladbrokes' spokesman Warren Lush said: "Punters believe the end is nigh for IDS. Bookmakers are under attack from malevolent forces and stand to pay out more than £50,000 if he goes before the end of the year."

James Slack returns on November 7

Updated: 11:13 Friday, October 17, 2003