A progressive advocacy group is launching a television ad campaign designed to pressure Republican Sens. Dean Heller and Jeff Flake to oppose Steven Mnuchin’s nomination as Treasury secretary. The ads, paid for by the group Allied Progress, are scheduled to begin airing Wednesday in the senators’ home states of Nevada and Arizona. The TV spots highlight the money Mnuchin made running the bank OneWest, which has been under heavy scrutiny for its foreclosure practices. Nevada and Arizona were hammered by the foreclosure crisis.