Labor is hoping to be re-elected for a fourth term at the March 15 election.
Mr Weatherill says the campaign will be a choice about the future of employment and the state's economy.
"Now there's an absolutely clear choice ahead of us," he said.
"A clear choice between the Labor party who will continue to build and invest in the new industries and the new jobs, and a Liberal party that will cut, and toe the Liberal party line."
Opposition Leader Mr Marshall said that the Liberal Party would be better suited to manage the state's economy.
"Jay Wetherill has no credibility whatsoever when it comes to budget numbers. It was only a few weeks ago he had a $400 million black hole leaked against him by his own party...so he has no credibility when it comes to numbers and I won't be taking an economic lesson from Jay Wetherill."
Despite polls showing greater voter support for the Liberal party, Mr Marshall said the election will be a close race.
"It's going to be very close and I think it's a tough ask for six seats in the South Australian parliament of just 47 seats. So that's why we're out campaigning everyday. That's why we're going to have work extremely hard up to the election."