The 65-year-old medical doctor retained his Calgary Mountain View riding. But the party lost four of the five seats it had held before the vote, as the New Democrats won a majority government and the long-governing Progressive Conservatives were relegated to third-party status.
"Alberta, you've spoken," Swann told supporters. "You've voted for change. And frankly, it's about time."
Swann told reporters later the party has been pronounced dead before, and yet it has persisted for decades.
But he said there's some soul-searching to be done.
"We have to go to Albertans and find out where we missed the mark, what kinds of issues that they want us to stand for that we haven't been — better communication," he said.
"The Alberta Liberal Party is not dead. We have to regroup and find out where we're not connecting with Albertans."
Swann admitted the result was "not what we'd envisioned," but he expressed optimism about Alberta's shift to the left with the New Democrats winning a majority government.
"Albertans are the winners. They called for change, they got change," he said.
"I think we're all pleased that we're going to see a more responsive, more open, and more progressive government."
He said he'd "absolutely" work with NDP premier-elect Rachel Notley as the two parties have many views in common.
Swann agreed to be the party's interim leader after Raj Sherman stepped down in January.
As for whether Swann stays on as leader, he said: "That depends on the Alberta Liberals."
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