Letter from the Political Editor: With 100 days still to go how will Cameron, Miliband and Co. keep us all engaged?

Another Monday, another speech from David Cameron on the economy, for the third week running. Today, Ed Miliband will unveil Labour’s 10-year plan for – you guessed it—the NHS.

With 100 days to go until the general election, the Conservatives and Labour are playing to their strengths in what looks like a campaign run on very familiar tramlines. No doubt they hope that a traditional approach will squeeze out the once-minor parties.

But they may be disappointed. Today’s ComRes poll for i shows that the Tories and Labour command the support of less than two-thirds of the electorate between them (61 per cent). So it is difficult to see how they can navigate their way to 7 May without talking about other issues that concern voters, such as immigration, inequality, childcare, welfare and education.

It is also hard to see how the parties will manage to engage the public for 100 days. We can’t blame them for not wanting to waste a moment when the election is so tight and the rise of Ukip, the Scottish National Party and the Greens makes it the most unpredictable contest since 1945. But the parties will surely need to pace themselves a little.

Who would win the “wealth versus health” battle that the Tories and Labour want to fight? It depends what is in the headlines when people vote. At present, the NHS dominates and has overtaken the economy and immigration as the most important issue facing the country. But that may not last. A eurozone crisis after the Greek election could easily turn the spotlight back on to the economy, to the Tories’ benefit. Labour cannot count its NHS chickens yet.

i@independent.co.uk