In the opening speech in the main conference hall, Brandon Lewis,the party chairman, told delegates that the UK was changing quickly, with the Conservatives at risk of being left behind.
In a long section devoted to party modernisation, Lewis cited the Tories record in areas such as equal marriage and reforming police use of stop-and-search tactics.
This was a proud record, he said, adding: But if we are honest, it hasnt done enough to change the perception some people have of our party today.
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Read more Earlier, an event on the conference fringe discussing how the Conservatives can gain more younger voters heard from a series of backbenchers, all of whom urged swift action.
Neil OBrien, who became MP for Harborough last year, noted that in the 2017 election there was a massive deficit between the Tories and Labour in terms of younger voters, and those from minority ethnic backgrounds.
At the 2015 election, OBrien said, the Tories lagged two percentage points behind Labour for voters in their 20s, and by four percentage points for those aged 18-24. Just two years later these deficits had shot up to 26 and 40 points behind.
The party was also doing increasingly less well among other groups whose numbers were rising, such as those with degrees, people who were unmarried, and those who rented their homes or live in cities, said OBrien, a former director of the Policy Exchange thinktank.
Read more All these different social bases of Conservatism are being eroded, he said. Either we have to do much better amongst these groups of people, or were going to go out of business as a political party.
Such structural changes would have an impact, he added: Its a bit like a beam that is rotting away, and eventually it snaps.
Facebook Twitter Pinterest The prime minister, Theresa May, at the Conservative party conference. Photograph: Sean Smith for the Guardian Another leading reformer, George Freeman, MP for Mid Norfolk who formerly chaired Theresa Mays policy unit, said the differences in how people of various ages voted was key for the partys future.
He said: It isnt just about, can we get more new people in the Conservative party, it is the dividing line in politics. And I think were on the wrong side of it. Its not too late to get on the right side of it, but it wont just happen.
While in 2010, just 28% of female voters under 25 voted Labour, by 2017 this had risen to 73%, Freeman said: We have a real problem, a massive problem. We have a demographic, structural and economic crisis in our political support base, and its getting worse, just with the passing of time.
Read more Solutions for the party raised at the event included radical changes to the housing market, a cut in interest rates for student debt, and an attempt to become less tribal over Brexit.
0:50 Lets come together and get best deal for this country, May tells Tories on Brexit – video The way Brexit was being debated in the party risked putting young people off the Tories for good, Freeman said. That religious zealotry, I think, is completely weird to a generation under 45, and I fear will lead us to Jeremy Corbyn having the keys to post-Brexit Britain.
At yet another event the former education secretary Justine Greening urged a new focus on social mobility, calling it an existential challenge for our party.
It was, she noted at a fringe speech, 31 years since the party last won a significant Commons majority, under Margaret Thatcher in 1987.
It is 31 years since we last truly carried the political argument in this country, she said. It means we stopped connecting with people a long time ago.
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