Will Cameron's Europe speech be a game-changer?

Six things that the Europe speech changed:

1. The Tory press is back

David Cameron has never enjoyed headlines this good. Even his bĂȘte noire Simon Heffer of the Mail praises him.

...but for how long?

2. The Tory backbenches are happy

MPs worried about losing their seats, as party activists and voters defect to UKIP, now have something to woo them back.

Europhobes loved the promise to end "ever closer union".

Pro-Europeans were relieved by the pragmatic tone of much of the rhetoric.

...but for how long?

Next week gay marriage will test their patience and many loathe the coalition.

3. UKIP's attacks on the Tories will now be blunted

Last night Nigel Farage attacked Ed Miliband. Some in UKIP will wonder if they should strike deals with Tory MPs, whether formally or informally.

...but for how long?

The EU budget row looms. If David Cameron comes back from Brussels with only a real-terms freeze will that re-light UKIP's fire?

4. The Lib Dems will get closer to Labour

A party led by passionate pro-Europeans - Clegg, Alexander and, perhaps soon, Huhne - will find the thought of another coalition with a Tory party committed to EU renegotiation increasingly unpalatable.

...talk of a Lab-Lib coalition will grow.

5. Labour will find it easier to woo big business

Although the Tories assembled an impressive list of business backers to write a letter to The Times today other business leaders - particularly of multinationals - may start to warm to the idea of a Labour government.

...making it easier for them to get elected.

6. The Tories will be more united ...

David Cameron took a leaf from Harold Wilson's play book by promising a renegotiation followed by a referendum to calm a battle raging in his party. It allowed Labour to get through two elections in 1974 without splitting.

...making it easier for them to get elected.

However, the divisions opened up by the referendum of 1975 led to the creation of the SDP in the early 1980s and Labour's wilderness years. It could happen to the Tories after 2017.

...but they may end up splitting.