Bernie Sanders is still outspending Hillary Clinton over the airwaves.
His campaign has spent $4.6 million in ads in the April 26 primary states of Connecticut, Maryland, Pennsylvania and Rhode Island, according to ad-spending data from SMG Delta.
By comparison, the Clinton campaign has spent $2.4 million in those same states. (Delaware is also holding a primary on Tuesday, but it shares a media market with Pennsylvania - so it doesn't show up in the SMG Delta numbers.)
On the Republican side, outside groups opposing Donald Trump spent just $100,000 in these April 26 states, while Trump's campaign aired $1.3 million -- in Pennsylvania alone.
Yet looking ahead to next week's primary in Indiana, anti-Trump forces have spent $2 million in ads, while Ted Cruz and his allies have spent an additional $2.2 million. By contrast, Trump has spent $960,000 over the airwaves in the Hoosier State.