'Secret weapon': How Trump is counting on Melania's RNC speech four years after she crashed and burned in plagiarism row

She is the first lady and the Trump campaign hopes Melania Trump won't be the administration's last with a 'secret weapon' speech on Tuesday that they are hoping will win over suburban women voters.

Ms Trump's prime time pitch, expected to focus on her husband's female empowerment credentials, comes after a 2016 campaign speech that failed the inspire the same enthusiasm as the 2008 Michelle Obama address it was accused of plagiarising.

Four years ago, Trump Organisation speechwriter Meredith McIver fell on her sword for inadvertently including parts of Ms Obama's Democratic National Convention speech in Ms Trump's opening night address to the Republican National Convention.

As goes Ms Obama in 2008: "And Barack and I were raised with so many of the same values: That you work hard for what you want in life; that your word is your bond and you do what you say you're going to do, that you treat people with dignity and respect, even if you don't know them and even if you don't agree with them. "And Barack and I set out to build lives guided by these values, and to pass them on to the next generation. Because we want our children - and all children in this nation - to know that the only limit to the height of your achievements is the reach of your dreams and your willingness to work for them."

So goes Ms Trump in 2016: "From a young age, my parents impressed on me the values that you work hard for what you want in life, that your word is your bond and you do what you say and keep your promise, that you treat people with respect. They taught and showed me values and morals in their daily lives. That is a lesson that I continue to pass along to our son. And we need to pass those lessons on to the many generations to follow. Because we want our children in this nation to know that the only limit to your achievements is the strength of your dreams and your willingness to work for them."

After the conspicuous similarities between the two speeches set off a couple of days of denial and finger-pointing, Ms McIver emerged to claim responsibility and offer her resignation for the apparent mix-up.

It happened, Ms McIver said in a statement at the time, after Ms Trump shared passages she liked from Ms Obama as examples of the messages she wanted to share with the American people.

"I wrote them down and later included some of the phrasing in the draft that ultimately became the final speech," Ms McIver said.

"I did not check Mrs Obama's speeches. This was my mistake, and I feel terrible for the chaos I have caused Melania and the Trumps, as well as to Mrs Obama. No harm was meant."

This time around, Ms Trump - whose first language is not English - has the resources of the White House at her disposal.

During an art exhibit opening that celebrated the 100th anniversary of women's suffrage on Monday, she gave what has been described as a warm-up preview of her RNC address.

"Since taking office, my husband and this administration have taken historic measures to empower and support women in the United States - and around the world," Ms Trump said.

"Under our administration, the child tax credit has been doubled. American women, who comprise over half of the workforce, experienced their lowest rate of unemployment in over 65 years,' she added. 'In addition to these achievements, this administration has filled many of its senior positions with women."

After the speech, White House adviser Kellyanne Conway told reporters that Ms Trump would be a standout of the Republican National Convention.

"The first lady's speech is amazing. It's the highlight of the week," Ms Conway said.

She should know.

Ms Conway is among a small entourage of White House aides that have reportedly been working with Ms Trump for days to craft Tuesday night's language. Other scribes are said to include East Wing chief of staff Stephanie Grisham and aide Marcia Lee Kelly.

It is in stark contrast to the speech writing process four years ago, when a pair of veteran Republican speechwriters, Matthew Scully and John McConnell, turned in an initial draft to Ms Trump, according to anonymous sources quoted in The New York Times.

That draft was reworked by Ms Trump with the help of her trusted aide Ms McIver, who had worked with Mr Trump's books, in the ill-fated attempt to make the speech her own.

Quoting a source close to the first lady, her 2020 speech will avoid deep policy in favour of her immigrant story and Donald Trump's agenda, according to The Washington Post.

Trump campaign strategists told the Post they hope Ms Trump will help attract suburban woman, who they fear are a weak spot for the president.