“I like the cross-party nature of all this.” So said a woman from Shropshire in an elegant pink cardigan who was standing next to me yesterday evening at the Remain rally in Birmingham.
She was a Liberal Democrat, and if David Cameron manages to win this referendum, it will be because he has managed to build a big enough coalition with voters in other parties, including Lib Dems, Greens and Labour, to outnumber his opponents in his own party and UKIP.
No wonder the Prime Minister declared in his peroration that if he were to boil his message down to one word it would be “Together”.
“Yes!” said the Lib Dem lady, who was called Jane Thomas. Perhaps because I happened to be surrounded by a band of Lib Dem activists, I was reminded, to my surprise, of the atmosphere when the SDP was founded in early 1980s.
Here was the same conviction that if only well-meaning people are allowed to work together in a grown-up fashion, British politics can be raised above the petty rivalries and demeaning squabbles which so often inhibit progress.
This style of politics comes naturally to Cameron. He loves to present himself as the leader of the Grown-Up Party, a Tory so unencumbered by ideological baggage that he can work with modern-minded people quite regardless of what traditions they come from.
And this was indeed a cross-party event. Having come to hear Cameron, I discovered that Harriet Harman, Gordon Brown, Kathy Warwick (head of the Royal College of Midwives), Brendan Barber (former head of the TUC), Caroline Lucas, Paddy Ashdown and Tim Farron were all speaking before him.
Brown was in rousing form. The meeting was held in the open air, outside the admirable, early-20th-century buildings at Birmingham University, and his words bounced off the Great Hall and back towards Old Joe, the astonishing campanile, inspired by a tower in Siena and over 300 feet high, which commemorates Joe Chamberlain, the great Liberal Unionist.
Cameron nodded, said “hear, hear” and clapped as he listened to Brown; and when he himself spoke, began by saying, “Wasn’t that a belter of a speech from Gordon Brown, and wasn’t that a belter of a speech from Tim Farron?”
Both men had indeed spoken well. The fear that we may be about to leave the European Union has lent them a kind of passionate energy, and no doubt they did not wish to disgrace themselves by performing badly.
But this was still a very odd meeting, for the audience of perhaps 200 people consisted almost exclusively of Remain supporters, including a substantial contingent of MPs.
Cameron, Brown, Farron and the rest were preaching to the converted. It is possible their words flew, via television, into the homes of the undecided, and had some effect there.
But this was a typically sanitised campaign event, devised to avoid controversy rather than confront it. Hecklers can nowadays vent their anger on social media, but are given very little chance to enliven public meetings by doing so.
Even as a journalist, I found it difficult to discover when and where this meeting was happening, at least until a few hours before it took place. The general public would not have known of it at all.
Earlier in the day, in Bristol, John Major had been deployed by the Remain campaign, but without the egg-throwing hecklers whom he defied to such good effect during the 1992 general election.
The Birmingham meeting was held in the constituency of Gisela Stuart, a prominent member of the Leave campaign, which somehow made it even odder that no dissent was heard.
Yet one should acknowledge the skill and tact with which Cameron manages a coalition of this kind. His most intractable problem lies with his Labour allies, who are having difficulty bringing their voters with them.
Hence the deployment last night of Brown, Harman and Barber, and of other prominent Labour figures in the Wembley debate on Tuesday night.
Cameron kept entirely to the economy and like the other speakers, avoided talking about immigration. “A strong economy is everything,” he said, wagging his finger in the way that he does at moments of heightened determination.
He has deep rings under his eyes, and more and more grey hairs, but in his checked shirt with rolled up sleeves, he remains the figure who in 2005 won the Tory leadership by putting his case better than his rivals did, and by appearing to go more for his shots, while remaining a reassuringly responsible personality.
Another of my neighbours, Lee Dargue, who at the general election stood against Stuart in Edgbaston for the Lib Dems, said that in Birmingham, support for Remain “wholly depends on where you go”. But he had also noticed, in the last 48 hours, a “shift in openness to listen to the Remain side”, in place of the previous, dismissive retort, “I’m not interested”.