Herman Cain has experienced a meteoric rise in the polls in recent weeks, and now the candidate who has vaulted into the top tier of the GOP presidential primary will need to add substance to the catchy, yet untested 9-9-9 plan, which forms the backbone of his economic policy. As Michael Fletcher reported, the devil is in the details:

The “9-9-9” plan that has helped propel businessman Herman Cain to the front of the GOP presidential field would stick many poor and middle-class people with a hefty tax increase while cutting taxes for those at the top, tax analysts say.

The plan would do away with much of the current tax code and impose a 9 percent personal income tax, a 9 percent business tax and a 9 percent national sales tax, which tax experts say would mean that low- and middle-income Americans would pay more.

“Right now, we have a strongly progressive income tax. High-income people are paying a higher share of income in taxes than lower-income people,” said Alan D. Viard, a former Federal Reserve Bank economist and a resident scholar at the right-leaning American Enterprise Institute. “That is a pattern that would be disrupted by adoption of the Cain plan.”

The 9-9-9 plan has helped define Cain’s candidacy. Coupled with his buoyant, plain-spoken style, it has helped transform the former long shot into a front-runner. Cain has touted the proposal’s apparent simplicity and fairness, but he rarely delves into details. His campaign Web site shows that the plan is only a step toward achieving his ultimate goal: to eliminate the Internal Revenue Service after replacing all federal taxes with a national sales tax.

Meanwhile, analysts said the 9-9-9 part of Cain’s vision would place a further burden on those hit hardest by the nation’s economic problems.

Roberton Williams, a senior fellow at the nonpartisan Tax Policy Center, is working on an analysis of Cain’s signature policy proposal. Although the plan’s details remain sketchy, Williams said that it would increase taxes for the poor and middle class, despite Cain’s statements to the contrary.

For starters, about 30 million of the poorest households pay neither income taxes nor Social Security or Medicare levies. “So for them, doing away with the payroll tax doesn’t save anything. And you are adding both a 9 percent sales tax and 9 percent income tax. So we know they will be worse off,” Williams said.

Herman Cain’s personal style and willingness to admit ignorance about certain issues has endeared himself to many voters. As Sandhya Somashekhar explained:

He opposes abortion, including in cases of rape and incest. He thinks Iran could be deterred from aggression by deploying more warships. And he is a proponent of privatized Social Security.

But just one topic — his “9-9-9” tax plan — has dominated Herman Cain’s rhetoric in this presidential race, helping to propel him to the top of Republican polls this month

And that has prompted questions about what else he stands for and whether he has the breadth of knowledge — particularly on foreign policy — expected of an occupant of the White House.

An examination of Cain’s words — his remarks as a radio talk-show host, as well as his writings, interviews and speeches — shows a man thoroughly steeped in conservative ideology. He has said that climate change is a scam, that he would not have survived cancer under the Obama administration’s health-care overhaul, and that the United States is on the brink of a socialist takeover.

In the style of an evangelist who can bring audiences to their feet, Cain has used his soapboxes to rebut criticism of the tea party movement, berate liberals and President Obama, and defend conservatives and Republicans against accusations of racism.

Reforming the tax code has been a keen interest since his days as the chief executive of Godfather’s Pizza in the 1990s. But outside of his tax ideas, Cain rarely gets into specifics. That is partly in keeping with his style of connecting with voters by communicating his ideas in basic, catchy terms.

“If you understand the simple concepts,” Cain writes in his recently published book, quoting an old teacher, “you will be able to deal with the complex concepts.”

It is also in keeping with his candor and the everyman persona he has cultivated on the campaign trail. Conservative audiences have found something compelling in his story, that of an African American who grew up in the segregated South and rose to become a successful business executive. And they have been energized by his passionate, humor-laced speeches.

Cain’s rise has made him a target for attacks from rivals looking to slow the rise in popularity of the Atlanta businessman. Rick Perry became the latest to attack Cain’s tax plan. As Perry Bacon Jr. reported:

Texas Gov. Rick Perry blasted businessman Herman Cain’s tax plan as “a big tax increase,” in an interview on Friday morning.

“It sounds pretty cool to just say 9-9-9, but at the end of the day, it is a big tax increase on some people out there that vote, that care,” the Republican presidential candidate said on ABC News’s “Good Morning America.”

Cain, who has surged ahead of challengers Perry and former Massachusetts governor Mitt Romney in some polls, is touting a proposal that would include a 9 percent sales tax, a 9 percent tax on individuals and a 9 percent levy on businesses. Independent analyses suggest it would reduce taxes on some Americans but drastically increase them for others.

Asked about his own dip in the polls, Perry sidestepped the question.

“Herman Cain is one of the most interesting people sitting on that stage. That’s for sure,” Perry said. “But I think when people look at what he’s talking about, when people look at his tax plan, when people try to make a decision about who do you really want running America, [it is] somebody that really knows how to create jobs, not somebody that’s got a catchy slogan.”

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