India, Oct. 20 -- Voters in Alberta, Canada's oil-rich western powerhouse, have delivered a resounding endorsement of national unity, rejecting a proposal to begin the legal process toward independence by nearly three to one, handing Prime Minister Mark Carney a significant political boost and quieting, at least for now, the most serious threat to Canadian territorial integrity since Quebec's independence referendums of the 1990s.

With more than 1.4 million votes counted, 76% supported remaining in Canada while close to 24% backed beginning a process toward separation, according to unofficial results from Elections Alberta.

Carney, who grew up in Edmonton and had thrown himself into the campaign with rare personal intensity, welcomed th...