It's just not true that the voters rejected the Attlee government, and opted for the Tories.

In fact in the 1950 election Labour got two and a half million more votes than the Tories, and scraped in with five more seats. In the 1951 election Labour got more votes than the other parties combined, and received the highest vote ever received by any party in an election. And lost. That's the British electoral system for you.

Of course the victorious Tories had the sense to appreciate stuff like that, and held to a range of policies for the next generation that were well to the left of the last Labour government in many ways.

If there's a split in the Labour Party it'll be the right who are the splitters, as usual.