The Liberal tumult over whether Ontario Premier Dalton McGuinty will run for the federal Liberal leadership took a new twist Thursday when senior Toronto Liberal MP Judy Sgro said she would be “shocked” if Mr. McGuinty jumps from a frying pan into a new cauldron, and predicted instead that his brother, Ottawa MP David McGuinty, is more likely the McGuinty who will challenge front-runner Justin Trudeau.