"Albertans have not been happy with their government," the incumbent premier told about 200 supporters in Calgary. "They have not been happy with a PC party that lost sight of the values of Albertans. That is what Albertans saw and that is what I saw too.
"We will not make the mistakes of the past."
Prentice is attempting to extend the PC party's four-decade dynasty, having just brought down a budget that increases taxes and runs a record $5-billion deficit.
He has spent the first week of the election campaign touting the spending plan, while challenging the opposition parties to provide more details on how they would deal with low oil prices.
Prentice on Monday reiterated his party's belief that the infrastructure plan will protect Alberta jobs and invest in services and infrastructure.
But he warned there are tough times ahead.
"We've been open with Albertans in talking about the challenges that we face, about how we're going to spend public dollars. I'm clear. It is not everything for everybody," he said.
"There are items on the wish list that we cannot afford under the circumstances we are currently in because tough times require decisive leadership."
Prentice's chief rival to the right, the Wildrose party, is campaigning on a plan to cut thousands of government management jobs and to delay infrastructure spending to attack the deficit without increasing taxes.
On the left, the NDP has blasted the budget as raising taxes for everyday Albertans while leaving the corporate tax rate alone.
NDP Leader Rachel Notley has called for the creation of a commission to deliver incentives to have more oil refined in Alberta rather than shipped abroad for processing.
Prentice once again challenged his opponents to offer more to the voter than "bare bones" ideas.
"I say to Albertans that while our plan is clear you need to ask others what they are proposing to build and what they are proposing to cut from the needs that we have identified," he said.
"They need to be clear and they need to be transparent with Albertans."
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