Anti-Donald Trump attacks top $35 million in advance of Tuesday primaries

Anti-Donald Trump protesters hold their protest signs outside a rally for Trump in Cleveland on March 12. (Rebecca Cook/Reuters)

A handful of independent groups have pummeled Donald Trump with $35.5 million worth of lacerating television commercials and other attacks in the run-up to Tuesday's primaries, hoping to dent and damage the Republican front-runner enough to keep him from securing the party's presidential nomination.

The results from today's contests will test the potency of the #StopTrump campaign and its wealthy backers, who have financed a string of hard-edged ads challenging Trump's businesses and character. Two new spots by Our Principles PAC, the super PAC behind nearly a third of the spending, spotlight the billionaire real estate developer's crude comments about women and violent language he has used on the campaign trail.

The biggest effort has been in Florida, which saw $15.7 million worth of anti-Trump spending by Monday. Another $5.3 million was spent in Illinois, where voters also go to the polls today. Ohio saw $1.35 million, while Missouri saw $1.24 million.

Altogether, Trump has fielded more attacks than all the other 2016 candidates combined. But the effort only began in earnest a few months ago, long after the New York businessman had established his front-runner status.

Weiyi Cai and John Muyskens contributed to this report.