Election 2015: Conservative plan to bridge 'north-south gap'
David Cameron says he wants to close the "growth gap" between the south and north of England by boosting transport, science, skills and infrastructure.
Growth in the north should at least keep pace with the south over the next five years, he said.
Plans include upgrades to the M62 between Leeds and Manchester and the A1 in Yorkshire, and one million apprenticeships.
Labour has said public services face "disintegration" due to Tory cuts.
Mr Cameron used a speech at the headquarters of Asda in Leeds to restate his party's ambitions for a "northern powerhouse", underpinned by devolution of economic, transport and care budgets to the north-west of England and new powers for Yorkshire.
He also visited the key marginal constituencies of Pudsey in West Yorkshire and Pendle in Lancashire, where the Conservatives are defending slim majorities against Labour.
Mr Cameron said Labour had "let down" voters in cities such as Leeds, Sheffield, Manchester, Liverpool and Newcastle where they had been the dominant political force for years and the Conservatives had scarcely any representation.
"My message to everyone in the north is simple: the Conservative Party is the party for you," he said.
"We have the ideas, the passion, the desire and, yes, the track record to create something special here."
The whole of England was benefiting from the economic recovery, he argued, with the north-east seeing the biggest rise in earnings in the past year and Yorkshire seeing the biggest fall in unemployment.
What he was pledging "is nothing less than the most important commitment to the north for decades: we're going to close the north-south growth gap. We're going to build a northern powerhouse, with more jobs and new investment coming to the north.
"The next five years will see a northern surge - and, economically, it will be the most exciting time to be here since the industrial revolution."
The north, he suggested, would "not get a look in" if a Labour government had to rely on the SNP for its support. "Transport projects in the north will get cancelled. Investment in science and industry in the north won't happen," he said.
Labour says most people are worse off than they were five years ago due to the government's austerity measures and that family budgets will be "devastated" if the Conservatives return to office, with child benefits and tax credits cut.
It has said it would devolve £30bn of funding to the English regions by 2020 and pursue a new industrial strategy, focused on increasing productivity, boosting business investment and harnessing green technology, a key industry in the north.
UKIP, meanwhile, has said it is on course to replace the Conservatives as the main opposition across much of the north of England.