President Obama has called on a special guest to help him make his case for economic fairness during his State of the Union speech Tuesday night: Warren Buffett’s secretary, Debbie Bosanek.

Bosanek will be among the guests in first lady Michelle Obama’s box in the House chamber when Obama delivers his third annual report to Congress at 9 p.m. She is the inspiration for the president’s call for wealthier Americans to pay a higher tax rate, known as the “Buffett rule,” which Obama is expected to highlight again in his speech.

The president will use the speech to offer his blueprint for creating a stronger economy, building on the populist themes of his fall jobs tour, which, the White House believes, offer a sharp contrast with Obama’s Republican presidential rivals.

The Buffett rule — which the president said was developed after the billionaire investor said he paid a lower effective tax rate than Bosanek, his secretary — forms a key component of Obama’s plan to boost short-term spending to help create jobs for the middle class.

And Bosanek will offer a sharp symbolic juxtaposition with the GOP on a day when Republican presidential candidate Mitt Romney released tax returns that show he paid an effective tax rate of 13.9 percent on his 2010 income of $21.6 million. He estimates payment of an effective rate of 15.4 percent on income of $20.9 million in 2011.

Obama “will be very clear about his vision, will be very clear about his principles ... about fair play and people getting a fair shot, economic security and protecting the middle class,” White House press secretary Jay Carney said.

Republicans have vowed to oppose any new revenue — including new taxes on millionaires — at a time when the national deficit continues to soar and Congress is trying to identify $1.5 trillion in budget cuts agreed to last summer.

Yet with the Bush-era tax cuts for the wealthy and middle class set to expire by year’s end, Obama could use his speech to demand that Republicans engage him in a broader restructuring of the tax code.

At the Capitol, House Speaker John A. Boehner (R-Ohio) said Tuesday that Obama’s policies “are just going to double down on what hasn’t worked.... It sounds like we’re going to see a rerun of what we’ve seen over the last three years.”

Asked about Obama’s expected focus on income inequality, Boehner argued that “the politics of envy, the politics of dividing our country is not what our country is all about.”

Obama’s GOP adversaries have cast Obama’s speech as the latest round in a series of “failed promises.” The Republican National Committee launched a television advertisement aimed at driving home that message in Washington and three cities in electoral battleground states: Charlotte, Norfolk and Grand Rapids, Mich.

The ad, titled “State of Our Union”, highlights the country’s high unemployment and mentions the Obama administration’s investment in the green energy company, Solyndra, which went bankrupt last year after receiving a $500 million, government-backed loan.

“This president is the king of promises ... but the problem is he does not follow through with anything,” RNC Chairman Reince Preibus said in a conference call with reporters Tuesday morning. “Obama speaks, lays out promises and recycles them in another speech, and Americans are left empty-handed.”

White House communications director Dan Pfeiffer told Fox News that the speech will include many ideas that Boehner has supported in the past, “things like putting construction workers back to work rebuilding roads and bridges.”

“First, I would encourage Speaker Boehner to hear the speech before he renders his colorful judgment on it,” Pfeiffer said in an interview on Fox’s “America’s Newsroom.” He added, “And the question for Speaker Boehner and all of the Republicans in the chamber tonight is, are they going to be willing to put country before party and work with the president to get some things done?”

In a video distributed to supporters over the weekend, Obama laid out the themes of his State of the Union speech, saying he would call for a “return to American values” where everyone receives a “fair shot” and is expected to “play by the rules,” a veiled shot at the Wall Street excesses that contributed to the financial crisis.

He reiterated previous calls for the manufacturing of more products “stamped with Made in America,” and said he wants to “get people the training they need so they’re ready to take the jobs of today and tomorrow.”

Obama also is expected to renew his calls for passage of provisions in his $447 billion American Jobs Act, most of which was blocked by Congress. Among those provisions is the extension, through the end of this year, of a payroll tax cut due to expire next month. However, Boehner has suggested that House Republicans might link approval of the Keystone XL oil sands pipeline, which the administration rejected last week, to the payroll tax plan.

In an election year fraught with hyper-partisan politics, Bosanek will not be the only guest in Michelle Obama’s box Tuesday night whose presence is heavy with symbolism.

The White House has invited former astronaut Mark Kelly to attend the speech, which will also be the final appearance in the chamber for Kelly’s wife, Rep. Gabrielle Giffords (D-Ariz.), who is retiring to focus on her recovery from the gunshot wound she suffered a year ago.

Obama delivered a stirring speech in Tucson after the shooting, stating: “At a time when our discourse has become so sharply polarized — at a time when we are far too eager to lay the blame for all that ails the world at the feet of those who happen to think differently than we do — it’s important for us to pause for a moment and make sure that we’re talking with each other in a way that heals, not in a way that wounds.”

As the 2012 campaign heats up, and the president prepares to address the nation again, those words seem as unrealistic as ever.

Staff writer Felicia Sonmez contributed to this report.

What do you want Obama to speak about in tonight’s State of the Union? Let us know in the comments, or by tweeting to the hashtag #mysotu.