Mexico's peso tumbled as much as 4.1% against the dollar on Monday and the local stock market fell over 2% after the ruling party scored a surprisingly strong election showing and looked poised for a super-majority that markets fear might bring constitutional change and diminish checks and balances. Claudia Sheinbaum won a landslide victory in Sunday's presidential election, which was widely expected. But the scale of the gains for the ruling Morena party and its allies...