Story highlights A pro-Donald Trump super PAC is ratcheting up criticism of Hillary Clinton

A new ad compares her email server to then-President Bill Clinton's dalliances with Monica Lewinsky

Washington (CNN) A pro-Donald Trump super PAC ties Hillary Clinton's private email server use to Bill Clinton's Monica Lewinsky scandal, in its first 30-second advertisement.

The spot, from the days-old group Rebuilding America Now -- launched by close Trump associate Tom Barrack with $32 million in commitments -- follows Trump's lead in casting likely Democratic nominee Clinton as untrustworthy.

It intersperses an August 2015 Clinton news conference in which she insisted that she had turned over every email on the private server she had used as secretary of state, and didn't send or receive classified material, with then-President Bill Clinton's famous January 1998 speech responding to the Lewinsky allegations. Bill Clinton at the time denied any past "sexual relations" with the former White House intern, which he famously had to later walk back.

The spot doesn't directly attack Hillary Clinton -- instead featuring only the Clintons' words.

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