Jeb Bush and Mitt Romney. (Brian Snyder/Reuters)

Someone recently quipped that people with car elevators shouldn’t complain about inequality, but I disagree. I welcome Mitt and Jeb and Marco (sounds like a cool boy band, no?) to the debate over inequality and poverty in America.

I am, however, not naïve. There are two tickets to admission to this debate.

First, part of what’s going on here is that these guys want to whack away at the president’s economic record, and they no longer have growth and jobs to beat up on. That doesn’t mean everyone’s benefiting from the growth — in fact, that’s the inequality point. But it does mean you can’t credibly do the old Rep. John Boehner thing and just wave each month’s jobs report around as a case against the president.

So when Romney complains about trends in inequality and poverty under Obama, one must consider the outside chance that he’s less interested about actually doing something about these economic blights than he’s running out of other stuff to rail about.

Second, you have to bring something to the table beyond the old canard that more growth will trickle down from the haves to the have-nots, more than “getting taxes and regulations out of the way,” more than shrinking government and repealing Obamacare. That is, you have to get beyond old rhetoric and into new evidence.

Instead, you need to bring something like this: the new report from the Children’s Defense Fund on how to lower child poverty by 60 percent.

I’ll get into details from the report in a moment, but let me be clear. I’m of course not suggesting that these conservatives adopt these measures. I’m saying they need to articulate their policy agenda in similarly granular terms, measure its impact on poverty or inequality, and suggest “payfors.”

If you’ve got such ideas and evidence of their effectiveness, absolutely bring them to the table. I and others will give them a sincere and objective look; Buddha knows, nobody has the ideas market cornered in this critical space. But don’t think you can just add the words “poverty” and “inequality” to your old campaign platforms and expect anyone to take you seriously.

(Just in case you think I’m being a haughty liberal here, let me point toward some recent posts by the smart conservative Jimmy Pethokoukis, who’s been making a similar case: “[the] economic reality [is] that cranking up GDP growth, while a necessity, may no longer be sufficient to lift all boats…”)

The table below shows what CDF proposed and what it cost, along with the simulation results of each policy (and their interactions) from microdata analysis by the nonpartisan Urban Institute (‘SPM’ stands for supplemental poverty measure, a metric that includes the impact of all of these policies). Increasing housing and nutritional (SNAP) support reduces child poverty by over 4 million. Combining numerous pro-work policies targeted at poor kids’ parents — subsidized jobs, expanded EITC (wage subsidy), higher minimum wage, and more help paying for child care — raises another 3 million kids out of poverty.

Source: CDF *The combined impact is less than the sum of the impacts of the individual policy changes because in some cases the same child would be lifted above poverty by more than one policy improvement. Similarly the cost of the nine changes together is less than the sum of the costs of the individual changes. ^ This includes spending going to all children, including those not lifted above poverty and those already above poverty.

(Two points on the minimum wage: one, the simulators assumed an increase to $10.10 in the federal minimum, and they built in some negative employment impact from the increase; two, the increase ends up saving $15 billion because its beneficiaries use fewer of the other services in the table.)

Before you conclude there’s no way any of the names above will go for these ideas, I should point out that Rubio has spoken favorably of expanding the EITC and the Child Tax Credit. Rubio and others (like Rep. Paul Ryan, who’s also given some support to expanding the EITC) have also stressed the importance of educational opportunity and marriage.

On the other hand, CDF pays the $77 billion price tag, which they point out is about 2 percent of annual outlays, by closing tax loopholes that benefit the wealthy and cutting military spending. That’s…um…not the R’s plan. In fact, any such expansions, including the ones noted above that some conservatives have leaned into a bit are wholly inconsistent with their budgets, which have cut deeply into low-income programs.

So let’s see, at a level of granularity that permits substantive evaluation, what they’ve got. When it comes to policy solutions to these difficult and persistent problems of inequality and poverty, all substantive evidence is welcomed, even if your car rides an elevator.