David Cameron writes:
"I'm on my way back from Norwich after celebrating Chloe Smith's historic victory in the Norwich North by-election. No-one was predicting a victory on this scale. A Labour majority of five thousand turned into a Conservative majority of over seven thousand.
"I'm proud of the campaign Chloe fought here - not just because of what it achieved, but because of how it was conducted. Chloe fought this campaign in a positive way about the issues that really matter to people on the doorstep. In contrast, the Labour campaign was full of lies and half-truths. It's time they learnt the lesson that trying to scare people by lying about your opponents does more damage to you than it does to them.
"But people don't just want straight talking on a local campaign level. They also want politicians to tell the truth about the challenges facing us as a country. They want to see that we recognise the change we need to bring to our politics, society and economy. That's why the Party that was frank and open in this by-election was the Party that won it. And that's why we need a General Election, so the rest of the country can have a chance to vote for the Party that will bring that change."