The real reason for the dip in Cameron's support:

Massie ofters another rationale:

There'll be a long and painful post-mortem is Cameron doesn't win but the reasons for that failure will, I hazard, have very little to do with his failure to be right-wing enough. British elections are won in the centre, these days, not on the extremes and it's puzzling that plenty of people seem blind to this seemingly obvious truth...

Cameron may - or may not be! - "under-performing" but if so that says as much about the mood and temper of the times (and the legacy of Tory blundering) as it does about his own positioning or mis-steps.

Buttonwood studies the latest polls and the betting markets. Rauchman is back in Britain:

[Clegg-mania] sets things up for Thursday’s debate nicely. Obviously, the other two leaders are now going to have to go for Clegg. And given that the debate is on foreign affairs, there are some juicy targets. I’m sure that David Cameron will attack Clegg on Europe and on immigration - both issues on which the Lib Dems are well to the left of the electorate.

Iain Martin looks at Labour's numbers:

UK Polling Report records that in the last ten polls, Labour has recorded ratings of 26, 28, 28, 26, 24, 27, 26 and - last night - 26, 28 23. That’s an average rating of 26.2% in the last three days. Those are atrocious numbers. To put them in perspective, in 1983 Michael Foot’s Labour party got 27.6% of the vote when it presented the electorate with a manifesto described by Gerald Kaufman as the longest suicide note in history.

David Blackburn and Daniel Finkelstein call this interview of Lord Pearson, leader of the  United Kingdom Independence Party (UKIP), "the worst interview ever given by a party leader in an election campaign":

Seumas Milne imagines a possible future:

[A] national unity coalition of all the main parties. Since our last peacetime experience of national governments in the 1930s, they have had a toxic name in Britain. But imagine if prolonged political deadlock after the election were to trigger a run on the pound or a bond-market crisis.

City pressure might then demand that only a broad-based government could make the cuts necessary to stabilise the markets. There's certainly enough ideological agreement between the Tories, the Lib Dem right and New Labour for a common programme – though it's hard to imagine all the Lib Dems or more than a handful of Labour MPs backing such an administration. It remains only an outside possibility, and such an elite stitch-up would certainly arouse ferocious public opposition. But the fact that it's no longer unimaginable is a warning that breaking the electoral mold may not have a happy ending.

And Judith O'Reilly identifies a burning political issue.

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