Trump suggests inviting Gennifer Flowers to the debate. Crossing a line?

A scandal more than two decades old could embarrass Democratic presidential nominee Hillary Clinton, but it could also backfire for her opponent.

The story broke in what The Washington Post described as “a trashy supermarket tabloid.” Early in 1992, a model and actress named Gennifer Flowers said she and Arkansas Gov. Bill Clinton, who was then vying for the Democratic presidential nomination, had engaged in a 12-year affair.

The revelation threatened to sink Mr. Clinton’s campaign. But he and his wife, Hillary Clinton, appeared on CBS’s “60 Minutes” immediately following the Super Bowl that year to denounce the allegations, ultimately securing the nomination and winning a first term.

Six years later, however, after securing a second term in the White House, Mr. Clinton admitted under oath that he and Ms. Flowers had engaged in sexual activity – but just once, he said, in 1977.

Mrs. Clinton and the American public were reminded Saturday of the embarrassing memory when current Republican presidential nominee Donald Trump tweeted that he should invite Flowers to the first debate of the 2016 general election.

Mr. Trump was responding to Mrs. Clinton’s decision to invite businessman Mark Cuban, a frequent Trump critic. It remains unclear whether Trump actually invited Flowers – whose first name he initially misspelled before correcting himself with a follow-up tweet within a few minutes – but she told multiple news outlets that she had accepted the invitation. CNN reports that Trump's spokesperson said that the invitation was not extended "formally" and that they "do not expect her to be there as a guest of the Trump campaign."

Flowers has called Mrs. Clinton an “enabler” and said the scandal from two decades ago is relevant to the 2016 race, as The New York Times reported.

Trump has himself been married three times, and his second marriage stemmed from an adulterous relationship during his first one. He has repeatedly used Mr. Clinton’s infidelity to attack Mrs. Clinton’s character. While the attempt to knock an opponent off-balance is not new, the nature of this latest blow is unprecedented and could backfire, as the Times’ Maggie Haberman and Megan Twohey wrote:

Campaigns often engage in psychological warfare when picking guests, as appeared to be the case with Mrs. Clinton’s choice of Mr. Cuban. But inviting a woman who had a sexual relationship with an opponent’s spouse would be in a different category.

If Mr. Trump does invite Ms. Flowers to be in the audience, he could also be taking a risk because he faces a potentially record-high gender gap with women, who might be troubled by such an aggressive and personal move.

The 90-minute debate, moderated by NBC Nightly News anchor Lester Holt, is scheduled to begin at 9 p.m. Monday without commercial interruption. Topics will include America’s direction, achieving prosperity, and security.