OTTAWA — A Conservative senator said Thursday he won't apologize for comments he made to a crowd of protestors, asking them to "roll over every Liberal left in the country." "The words I used may not have been as artful as I would have liked and certain individuals are happy to misinterpret them to suit their own self interest," Saskatchewan Sen. David Tkachuk said in a statement.Tkachuk said he was asked by the Greater Ottawa Truckers Association to speak to a few hundred "United We Roll" protestors gathered on Parliament Hill Tuesday.It was a figure of speech.