Clark, who is the party's leader, beat Tory Education Minister Gordon Dirks in Calgary Elbow on Tuesday, a seat once held by former premier Alison Redford.
The next challenge will be raising the Alberta Party's profile elsewhere in the province.
"It's a step forward, but it's only one step. There are no shortcuts to building a political party," Clark said in an interview at the party's raucous election-night headquarters.
With the Progressive Conservatives ousted after more than 44 years in power, the days of political dynasties in Alberta are over, he said.
"We're going to see a natural cycle of democracy where we kick the government out every now and then."
Clark said he's expecting less of a "hyper-partisan" bent to Alberta politics and a greater focus on what legislature members can do to address issues in their constituencies.
He said flood mitigation will be one of his top priorities in Calgary Elbow, which was one of the areas hardest hit during the 2013 deluge.
The Alberta Party has been working to unite voters in the middle of the political spectrum against the Progressive Conservatives.
While Clark is the first elected member, the Alberta Party has been represented in the legislature before. Liberal Dave Taylor crossed the floor and sat as a member in 2011, but didn't run for re-election in the 2012 election.
Clark said the NDP's landslide victory was probably due to a combination of anger at the Progressive Conservatives and excitement about what NDP Leader Rachel Notley had to offer.
"I always thought from the very beginning that (former PC leader) Jim Prentice missed modern Alberta and what today's Alberta really is.
"And full credit to Rachel Notley — she tapped into something."
For whatever reason, Albertans have made a decision to leave the old politics behind, Clark said.
"They moved on from the PCs. The vehicle they've chosen is the NDP."
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