Rachel Notley says her goal is to be the next premier.
Notley launched her campaign outside the legislature, saying Albertans need a government that focuses on families, health care, education and jobs.
She says people are looking for an alternative to what she calls the old, tired Progressive Conservative government.
Premier Jim Prentice has called the election for May 5.
The NDP has confirmed 85 candidates and the final two contested constituencies are to be settled this week.
The party has four seats in the legislature, all in Edmonton. But Notley says the NDP is in the best position in decades — with more resources and quality candidates — to win power.
"I'm running to be premier. I don't run to be second place," she told reporters Tuesday in Edmonton.
She said she's seeing unprecedented support for the NDP across the province.
"We know that Albertans are truly looking for an alternative and my message to them is that the NDP is that alternative. And when you call an election, anything can happen."
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