It may be that support for the Conservative party is at or near a peak. But that does not mean a Conservative majority is impossible.
Thanks to our antiquated voting system it is quite possible for Conservative support to remain unchanged and pick up more seats, so long as Liberal support falls. While the Conservatives would like to pick up lost Liberal support, Liberals switching to the NDP can also enhance the Conservative seat count. Everywhere Conservatives run second to Liberals a Liberal voting NDP is a good thing. While this vote splitting flaw with First Past the Post election systems is no great revelation, it does explain recent examples of Conservatives being nice to the NDP.