The Conservatives' decision to launch an all-out attack on Unite and its political director, Charlie Whelan, reveals concern that the union's marginals strategy will hurt the party. The pugnacious Whelan, once Gordon Brown's spin doctor, is using Obama-style peer-to-peer marketing to attract swing voters to Labour.
Whelan, a regular No 10 visitor, is tipped for a formal media role once the campaign proper begins. All this has led Michael Gove to claim,hyperbolically, that a "Whelanist tendency" had seized the Labour Party. But the union man has certainly returned to a prominence few expected.
Following George Galloway's success at the last election, could Respect pull off another surprise victory this time around? The party leader, Salma Yaqoob, who finished second in Birmingham Sparkbrook in 2005, is standing in the neighbouring Hall Green seat where Labour's Roger Godsiff is defending a notional majority of 4,191. Yaqoob is popular in the area, a third of which is Muslim, and she has been helped by the local Green Party's decision to stand aside and endorse Respect.
David Cameron may be denied a majority at the election but Northern Irish politicians may yet hand him an effective majority in the Commons. First, Sinn Fein's five MPs refuse to take their seats, because to do so would mean swearing an oath of allegiance to the Queen. Second, the new Ulster Unionist-Conservative alliance means that any MP elected under the joint banner will take the Tory whip. But the fate of John Major, whose 1992 majority of 21 was wiped out in by-election defeats, is a reminder of the hazards of a small majority.
East Lothian Labour is in chaos. Anne Moffat MP faces deselection, after missing important constituency meetings and failing to vote in the European elections. But she accuses "vindictive" party members of hampering recovery from a brain haemorrhage.