Grant Shapps, the Conservative chairman told The Independent: "The benefits system has needed attention for a long time. The last Labour government spent billions on welfare, but their approach lacked results.
The poster is being displayed at six locations across London
"During that administration, welfare spending increased by 60 per cent, but that increase was never reflected in the number of people getting back to work.
"In fact there were half a million more unemployed people by the time Labour left office, compared to when Blair was elected."
Labour however, contend that those who will be punished by capping benefits at 1% until 2014 will be soldiers, nurses and teachers, not the "shirkers" the coalition is saying the move targets.
Ed Miliband told Channel 4 News: "What we're voting for is a fairer way forward ... the idea that at a time when you're cutting taxes for the richest in society, that you penalise the most vulnerable in society and those going out to work - those people doing the right thing, the strivers that Mr Cameron says he stands for - it doesn't add up.
"It's the wrong thing to do and the Labour party is taking absolutely the right decision."