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Washington (CNN) -- President Barack Obama is expected to amplify income inequality in his sixth State of the Union address as the gap widens between rich and the poor in the United States.
The timing is prescient: Obama's address comes within weeks of the 50th anniversary of President Lyndon Johnson launching the "War on Poverty" in his first State of the Union address.
Since then, poverty has held an uneven place in American political discourse even as the number of poor people grew from 37 million in 2007 to nearly 50 million, or 16 percent of the population, in 2012, according to U.S. Census figures.
Jack Kemp, the longtime Republican congressman and GOP presidential and vice presidential candidate, tried and failed to launch a conservative "War on Poverty" more than two decades ago.
John Edwards, the 2004 Democratic vice presidential nominee and 2008 White House candidate, made poverty central to his political platform during both unsuccessful campaigns.
But Edwards' political career hit the rocks after his second presidential bid. He admitted to an extramarital affair and lied about having a child out of wedlock. Edwards was shunned from politics and his anti-poverty platform faded.
"I think the issue was put on the shelf at the same time he was," said Harrison Hickman, a political researcher and consultant who has worked on dozens of political campaigns, including both of Edwards' presidential races and his successful 1998 Senate race.
In an e-mail exchange with CNN, Edwards, who is back practicing law, discussed his campaigns and American politics exclusively.
He said Democrats and other politicians have largely ignored the issue.
"Poverty has been non-existent in the American political dialogue," Edwards wrote. "Poverty should be and has been at times at the heart of the Democratic Party. The Democratic Party is at its best when it stands up for the little guy."
Edwards is not a "little guy."
Before his career in politics, he made millions as a trial lawyer in North Carolina. As a Senator from a conservative state, he didn't always fight for that "little guy," either.
He ran his 1998 Senate campaign as a centrist and legislated that way, too. The National Journal determined Edwards to be one of the more conservative Democrats in the Senate.
"Even now, after a year and a half of watching Edwards closely, I can't say for sure who exactly he is or what he stands for," Charlie Hurt, a journalist who covered Edwards for the Raleigh News & Observer, wrote in a profile for Washingtonian Magazine in 2003.
"I came to Washington to find the real John Edwards. Politically, at least, the candidate still seems to be searching for him, too," Hurt wrote.
But that was before Edwards found the platform that defined his presidential runs.
Edwards told CNN that he found his voice in Iowa during his first national campaign in 2004.
There, he said longtime Democratic political activist and friend, Roxanne Conlin, "pushed me to become more vocal about" poverty.
Conlin affirmed the account. She said she supported Edwards and knew that, like herself, he grew up in poverty and knew that the issue was important to him.
"It shapes your life," she said in a recent interview with CNN. "He is a rich guy, but if you've ever lived in the other America you never forget it."
On the campaign trail, Edwards often spoke about his humble roots as the son of a mill worker who grew up in the small, poor town of Robbins, North Carolina.
"I saw my father, a man whom I love deeply, treated with disrespect and little dignity because he had no money or education," Edwards said in his exchange with CNN. "Issues of class and economic inequality were deep and engrained (sic) in me from the time I was young."
Conlin said, however, that Edwards had to be sold on the idea to organize an entire campaign around poverty.
She said the moment she urged Edwards to take it on was burned into her memory. It was in the conference room of her Des Moines law office in 2003.
He was "hesitant," she said. "He wanted more information. He wanted to understand what [the campaign] would look like."
Few Democratic candidates have talked about poverty since Johnson launched his program during his 1964 State of the Union address. Robert F. Kennedy's poverty tour just a few years later gave it prominence.
"We as Democrats had permitted ourselves to be bullied by Republicans to shut up, and it was morally wrong," Conlin said, referring to a move away from direct poverty-alleviating measures of the 1980s and 1990s and focus on deficit reduction.
"People argued that it was bad politics and that more successful candidates needed to be more sympathetic to business and emphasize the middle class," Hickman added.
During the time of Conlin's intervention, Edwards was barely registering in the polls among his Democratic rivals.
News outlets called him a "second-tier candidate" with little chance of beating Vermont Gov. Howard Dean and Missouri Rep. Richard Gephardt.
But Conlin persuaded Edwards that an anti-poverty message would appease Iowa Democratic activists.
And she gave him a draft known as the "Two Americas" speech.
Edwards decided to jump in feet-first. He had to do something, after all, or he would not have a shot at the nomination.
"When we got down to the point when we weren't winning as many votes as we wanted to, Edwards' point of view was he was going to talk about what mattered to him," Hickman said.
Weeks before the Iowa caucuses, Edwards pulled out a polished version of the speech:
"Today, under George W. Bush, there are two Americas, not one: One America that does the work, another America that reaps the reward. One America that pays the taxes, another America that gets the tax breaks. One America that will do anything to leave its children a better life, another America that never has to do a thing because its children are already set for life. ... One America that is struggling to get by, another America that can buy anything it wants, even Congress and a President."
His popularity soared, propelling him to a shocking second-place finish in Iowa, sustaining his campaign and landing him the spot as John Kerry's running mate in 2004.
"It was a good idea because it was, by far, the most important platform of our campaign," Edwards told CNN. "And it still is a very important issue that needs much broader awareness and work behind it."
But with Edwards' sudden exit from politics, the issue is no longer amplified.
"One of the great tragedies of his absence from the political scene is that no one is really calling attention to it," said Hickman.
And common perception remains: Talking about the poor isn't politically advantageous.
"Poor people typically don't vote, they don't contribute to candidates, and for the most part, politicians feel no connection with them," Edwards said.
In an interview shortly after he dropped out of the presidential race in 2008 -- unable to overcome Hillary Clinton's machine and Obama's star power -- Edwards said he bucked conventional wisdom.
"You don't know idea how many times I've heard from political consultants, you have to talk about the middle class. You can say inequality. You can't use the word poverty," he told "NOW on PBS" host David Brancaccio in 2008.
David Axelrod is more widely known as the mastermind behind Obama's catapult to the presidency. But when he worked for Edwards in 2004, a source, who asked for anonymity in exchange to speak freely, said Axelrod firmly believed "you can't run for president talking about poverty."
Axelrod took issue with that account. He told CNN that he has "no problem" with poverty as an issue, but said the decision made so late in the Democratic primary seemed illogical.
"It struck me as a little cynical," he said. "With a country mired in war, a middle class under siege and myriad other big challenges, it also seemed incomplete."
Axelrod wasn't alone. The New York Times hailed Edwards for taking on such an important issue in 2008 but questioned the depth of his principles since his tone shifted since his days in the Senate.
Axelrod didn't return for Edwards' second run and hitched on to a more successful candidate -- and campaign.
Obama: a different approach
While Edwards continued to talk about poverty during his 2008 run as well, Obama's presidential campaign took a different approach.
Instead of highlighting "two Americas," he imagined a unified America on multiple fronts -- race, class, sex, religion and ideology.
He rarely used the words "poor" or "poverty" on the campaign trail -- a theme that has continued through his presidency.
A study by the Center for Applied Research in the Apostolate at Georgetown University from 2012, found that Obama has spoken about to or about poor people less than any President the center analyzed, which started with John F. Kennedy. While addressing economic issues, Obama spoke about the middle class 51% of the time and the poor just 26% of the time.
After Obama, President George H.W. Bush, a Republican, addressed poverty 50% of the time -- twice as often as Obama.
That's not to say that Obama hasn't sought to help the poor.
Obama's signature domestic achievement of his presidency to date, the Affordable Care Act, includes an expansion of the Medicaid health coverage program for the poor, which was created under Johnson's "War on Poverty."
And Obama's expected to continue his call for an increase in the minimum wage, a policy that poverty advocates, including Edwards, believe will help the working poor.
Obama frames the economic debate through the prism of the middle class. Though he's expected to talk about income inequality in his State of the Union speech, he is unlikely to talk directly about the poor.
Instead, it will be about "restoring opportunity for all Americans," White House spokesman Dan Pfieffer told CNN's Candy Crowley on "State of the Union" on Sunday.
Between presidential races, Edwards founded the poverty center at his law school alma matter, the University of North Carolina at Chapel Hill.
"I personally saw thousands of people, mostly women, in poverty centers around America who were doing everything possible to build a better life for themselves and their children. But, they were faced with impossible obstacles," Edwards said. "I believed then and believe now, that America is better than that and our leaders should take a stance and help these people help themselves."