Bernie Sanders is outspending Hillary Clinton over the airwaves by nearly a 3-to-1 margin in Wisconsin, while the campaigns and outside groups opposed to Donald Trump have the overwhelming ad-spending advantage, according to the latest data from SMG Delta.
In Wisconsin, which holds its primary on Tuesday, Sanders' campaign has spent $2.4 million in ads, versus $931,000 for Clinton's campaign.
In the GOP race, outside groups opposed to Trump -- Our Principles PAC and the Club for Growth -- have spent $2 million in ads, while Trump's campaign has spent just more than $500,000.
Ted Cruz and his outside groups supporting him have spent an additional $1.4 million in ads, while John Kasich and his allies have kicked in $970,000.
