Did it actually ever look likely? It was unclear from this side of the pond, but it seemed like the defeat was a foregone conclusion in many circles, and the chief surprise was the margin of defeat.
Quite often in the lead up to a controversial vote there are people saying that they will vote against their party's wishes who when it comes to it actually either abstain or vote in line. This is politics, deceit and bluff are part of the game.

There is also a significant amount of pressure that can be applied to a party member to vote in line. Sometimes you see MPs who are initially very vocal about something suddenly shut up and toe the line, usually they have been intimidated by party seniors.

On this occasion I guess Blair over-estimated the level of bluff and the amount of MPs that could be intimidated into voting for.
I thought so. The whips can really lean on people when it matters to them. Tone's never lost a Commons vote (as PM) before today.