Image caption Ann Widdecombe voiced the feelings of many at the meeting

David Cameron could only dream of this sort of fervour when he delivers his big conference speech on Wednesday.

But it would have been a very different kind of atmosphere had the Conservative leader dared to venture into Birmingham Town Hall on Monday lunchtime.

Mr Cameron has angered a swathe of his party with his commitment to legalising gay marriage.

And a significant number of them - about 1,000 in total - ran the gauntlet of protesters outside the venue to voice their anger, dismay and, in many cases, sheer incomprehension at his stance.

The fringe event - normally sedate affairs, with bored activists picking over sandwiches - felt more like a revivalist meeting. They shouted, they cheered. They cried out "Amen".

It fell to Ann Widdecombe to put into words what they were feeling - in particular their anger at being labelled "bigots" by those campaigning for the legalisation of gay marriage.

"Is it bigoted to recognise that the complementarity of a man and a woman in a union open to procreation is unique and cannot be replicated by other unions?" she asked, to cheers.

"The real bigots, those who really deserve to be described as such, the real extremists, the real nasties, are those who believe that those who dissent from their views have no right to do so and that the state itself should silence them."

She poured scorn on the idea that the words "husband" and "wife" could be replaced in official documents by terms such as "partner" or "progenitor".

'Damage'

The proposal will throw up so many complications and lead to so much prejudice against teachers and foster parents who oppose gay marriage that it would be a disaster for Britain, she argued, not to mention the Conservative Party.

Image caption Protesters staged a noisy demonstration outside the venue

"It's come about because David Cameron has a very personal conviction - I do not deny wish to deny that - but unfortunately it is doing a lot of damage to the party."

For many of those present, the idea of same sex couples marrying in church is an affront to their Christian beliefs.

But, for others, it illustrates the yawning chasm between the "trendy" metropolitan world Mr Cameron inhabits and the values of traditional Conservatives.

"Why is he doing it?" asked one delegate, after the meeting.

"Why is he destroying the Conservative Party with this? Because he is. I have already told my MP if he votes for the change I will not vote for him again.... It's suicidal really."

Gayle Brown, a retired religious education teacher, said she would not have pounded the pavements at the last election if this proposal had been in the party's manifesto.

"This is a truth that has been in the arena for 2,000 years. I don't think even David Cameron has a right to challenge that," she told BBC News.

The Coalition for Marriage, which organised the event has collected more than 600,000 signatures calling for the coalition to drop its proposals.

If it goes to a free vote in the Commons, they accept that they will probably lose but they hope to put enough pressure on Conservative MPs, and those from other parties, to get the government to shelve it.

Former Archbishop of Canterbury Lord Carey spoke about the special place marriage between a man and a woman had in Christian teaching, adding: "The matter is so serious... that we cannot allow politicians to plunder something as sacred as this institution."

He said he had the "highest regard" for David Cameron but hoped the prime minister would have a change of heart.

And then - in a way that only a high-ranking member of the clergy can - he put the boot in.

He accused Mr Cameron of pursuing the gay marriage issue not out of principle but out of political expediency and to make the Tory party seem more modern.

"If you are not bothered about the real inequality in the country, which is one between the rich and the poor, if you are not doing enough about that then please don't dabble in something which is such a wonderful institution," said Lord Carey.

"We need to strengthen marriage, not weaken it."

'Nazi Germany'

He also risked controversy by appearing to compare anti-gay marriage campaigners to persecuted Jews in Nazi Germany.

Calling for a "sensible debate", he suggested verbal abuse of Jewish people marked the beginning of the totalitarian Nazi state.

"Remember that the Jews in Nazi Germany, what started it against them was when they were called names, that was the first stage towards that totalitarian state," he said.

And what of those outside the venue who, despite their trade union banners and anti-Tory slogans, find themselves on the same side as the Tory leader?

Geoff Dexter, of West Midlands Love Music, Hate Homophobia, who organised the protest, says Mr Cameron is merely reacting to pressure from groups like his and from wider society.

Like the Coalition for Marriage, he claims public opinion is on their side.

"We need to move forward. We need equality in every aspect of our lives and this is a group of people whose views are outdated," he added.