Canadian Election a Tossup as Trudeau Tries to Stay in Power

Liberal prime minister and his Conservative challenger seek to win over voters with tax-relief measures

OTTAWA—Early Canadian election results suggest Prime Minister Justin Trudeau’s Liberal Party lost some ground but retained the bulk of its support in Atlantic Canada, giving the incumbent Liberals an edge over their Conservative rivals.

Results in Atlantic Canada, which account for just under 10% of all the electoral districts up for grabs in Monday’s election, showed the Liberals had either won or were leading in 25 of the 32 seats in the region. During the last Canadian election in 2015, the Liberals swept Atlantic Canada,...