Big data is being cast as the enemy of the day- but it's legal and common in a lot of ways, especially in politics. How has it been used in Canada's elections, and how might it be used in 2019? What other ways are elections changing? And Kathleen Wynne and Philippe Couillard are both Liberal premiers running for re-election- just with opposite fiscal strategies. Why, and how are those working so far? Rosemary Barton is joined by Chantal Hébert, Andrew Coyne and Paul Wells.