By Fergal Smith TORONTO, Jan 17 (Reuters) - The Canadian dollar strengthened against its U.S. counterpart on Tuesday as investors raised bets on a Bank of Canada interest rate hike this month following domestic data showing persistence in underlying inflation pressures. Canada's annual inflation rate eased more than expected to 6.3% in December as gas prices came down, but core measures remained little changed from the previous month. Underlying measures of inflation "are a little bit stickier" than the headline, said Michael Greenberg, SVP and portfolio manager at Franklin Templeton Investment Solutions.