Dwight Ball, the former interim provincial Liberal leader, won the race on the third ballot in a preferential voting system.
"We are ready to govern, and together we will build a brilliant future for Newfoundland and Labrador," he told about 300 cheering supporters in a hotel ballroom in St. John's.
"I will not let you down."
Ball takes the helm at a time when supporters are more hopeful than they've been in years for the next provincial vote in October 2015.
For the first time since the Progressive Conservatives swept to the first of three consecutive majority wins in 2003, the Liberals are topping recent polls.
Ball said voters across the province are ready for change.
"People want democracy restored. They want honesty, accountability, integrity."
He said his first step as premier would be to repeal perceived access-to-information restrictions under the Tory government.
"This is the first step in ending the arrogance and restoring accountability," said Ball.
Just over a week of voting wrapped up at noon Sunday, with 63 per cent of the roughly 38,000 eligible voters casting ballots, the party said.
The party used a one-person, one-vote system that allowed voting online and by telephone with personal identification numbers.
Voters were asked to rank five candidates by preference.
The weighted process allotted 100 points to each of 48 provincial districts. For example, a candidate who was the top choice of 20 per cent of voters in a district in the first count got 20 points. Those with the fewest points or less than five per cent of the total dropped off each ballot and their points were redistributed according to second choices on those ballots.
Danny Dumaresque, a Liberal government member under former premier Clyde Wells, dropped off after the first count along with current Liberal Opposition member Jim Bennett. Businesswoman Cathy Bennett dropped off the second count.
Ball won on the third count with 2,832 points.
Runner-up Paul Antle, a Harvard-educated businessman who won 1,967 points, said he still plans to run for the Liberals in 2015.
The party has much work to do if it's to build on apparent momentum. Party debt of about $800,000 is a major issue along with the need to mobilize volunteers.
The Tories now hold 35 of 48 seats in the house of assembly. The Opposition Liberals have seven seats and the NDP has three members after two left to sit as Independents after a very public leadership blow up three weeks ago.
There is one vacancy since Premier Kathy Dunderdale lost one of her most senior cabinet members with the resignation of former Finance Minister Jerome Kennedy last month. He stepped down to resume practising law.
A byelection is set for Nov. 26 in the Conception Bay North district of Carbonear-Harbour Grace.
It will be cast as a test of Tory support and whether the Liberals can take advantage of the government's bleak approval ratings.
An August poll by Halifax-based Corporate Research Associates suggested a satisfaction rating of 31 per cent for Dunderdale's administration — down from more than 80 per cent under former premier Danny Williams before he quit politics almost three years ago.
The Tory government has been under fire for much of the last year. It has had to defend a cost-cutting spring budget that slashed 1,200 public sector jobs, access-to-information changes, and risks linked to the $7.7-billion Muskrat falls hydro project in Labrador.
Opposition critics also pounced after the last budget forecast a deficit of $564 million this fiscal year due to flubbed oil price predictions and less demand as world economies slowed.
If she's worried, Dunderdale isn't showing it.
She brushed off any threat of a Liberal resurgence last week when asked about the leadership race.
"This is their sixth or seventh leadership we've been through with the Liberals since 2003," she said Thursday outside the legislature. "So, no, I can't say that I'm getting super excited about it or perturbed about it."
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