Canada Tory lead "locked in," pollster says

* Conservatives slip but maintain 10-point lead

* Liberals near the poor showing from last year's election

* Another minority government would be most likely

OTTAWA, Nov 12 (Reuters) - Canada's governing Conservatives are maintaining a double-digit lead in public support over the rival Liberal Party though they have slipped from polling levels normally seen necessary to form a majority government.

An Ekos poll released on Thursday showed the Conservatives at 36.6 percent, down from 37.4 percent a week ago, and the Liberals at 26.6 percent, down from 26.8 percent.

"The parties now appear to be fairly 'locked in' to support levels consistent with the last election. There does not appear to be anything in the handling of the H1N1 (flu) crisis which is likely to disrupt that pattern," Ekos President Frank Graves said.

"What must be most worrisome for the Liberals is that while the Conservatives have slipped somewhat in the last month, none of that shift has accrued to them."

The Conservatives won re-election in October 2008 with a minority government, one that requires the support of at least one opposition party. The current poll standings show that would again be the most likely result.

The Liberals are less than half a point above their 2008 election result, their worst showing in terms of percentage of vote in more than a century. They came in third place in four partial elections held this week to fill vacant seats.

Their support deteriorated after deciding in September to try to force a new election.

Ekos has the leftist New Democrats at 16.8 percent, the Greens at 11.2 percent and the separatist Bloc Quebecois at 8.8 percent.

The automated telephone survey from Nov. 4-10 covered 3,502 Canadians, a sample size that should be accurate to within 1.7 percentage points 19 times out of 20. (Reporting by Randall Palmer, editing by Vicki Allen)