On April 23, a Senate bill that would have raised the federal minimum wage to $10.10 an hour failed to clear a Republican filibuster. The debate over whether to raise the federal minimum wage will most assuredly be at the center of the fight for U.S. Congressional seats going into the 2014 mid-term elections. The issue is a well-trodden battleground in American politics, with Democrats arguing that the nation's lowest earners are in desperate need of economic relief, while Republicans warn that a rise in the price floor for labor will hurt employment in the midst of a prolonged period of slow job growth. The months leading up to November promise no shortage of office seekers making vague references to economic studies that irrefutably prove the righteousness of their position. But for the economists whose work serves as ammunition in this theater of the political shooting war between conservative and progressive factions, questions about the minimum wage have less to do with right or wrong than with who, when and how.

Analysis of the minimum wage in the United States offers a range of easily accessible, countable statistics. In the past 23 years, for example, the real value of the minimum wage has not risen above the lowest levels it saw between 1955 and 1981. More than half of minimum wage earners are under the age of 25, and two thirds of them are women. When it comes to the macro-effects of the minimum wage as a policy issue, the math becomes less clear.

The broader effects of changes to the minimum wage, however, are harder to pinpoint. Isolating situations where differences in local minimum wages aren't accompanied by other, potentially confounding economic differences is a difficult task. Further complicating matters is the fact that economists seem unable to reach a consensus on how potential effects of a wage floor might manifest in a broader economy. Most Americans are familiar with the use of unemployment rates as a convenient barometer for overall economic health. However, job growth, consumer spending and employment turnover rates are also potentially telling economic indicators that economists argue may be more directly affected by raises to the minimum wage.

It can't help that adding new research to the existing literature about this topic is akin to volunteering for a level of public criticism, second-guessing and skepticism, from enlightened amateurs, that few economists ever get to experience.

"I normally work on far less controversial issues like charitable giving," says Jonathan Meer, an assistant professor of economics at Texas A&M who co-authored a study last year on the negative impact of high minimum wages on employment growth. He says intense feelings about the minimum wage as a political issue make it a delicate topic of study, adding, "The economics have really gotten mixed up with the politics."

Daniel Aarinson, vice president and director of microeconomic research at the Federal Reserve Bank of Chicago sums up the atmosphere surrounding minimum wage studies even more concisely. "This is a hornet's nest," he says.

Taken alone, Aarinson and Meer's recent studies seem to tell starkly divergent stories about the potential fallout of a hike to the minimum wage. Aarinson helped conduct a study, last year, that showed significant increases in spending by low-wage workers in the months following a jump in local minimum wages without any significant accompanying change in unemployment levels. The boost in spending was far greater than the value added to low-wage paychecks higher minimum wage.

Meer, on the other hand, co-authored a study which found that job growth in economies with a higher minimum wage tended to be slower than in comparable areas with a lower minimum wage. Meer found that people didn't lose jobs as a direct result of the higher minimum wage, but once jobs were vacated, businesses were less likely to try and fill them.

"It's not that people are getting fired," says Meer. "Its that people may not ever get hired in the first place."

So which is it? Does a higher minimum wage inject more money into economies, by putting cash in the hands of people who are likely to spend it right away? Or does government meddling in the job market deter businesses from hiring?

The answer, it turns out, is a little more complicated than that. While Meer and Aarinson's studies both looked at raises for minimum wage workers, the beneficiaries of those raises were very different.

Those most effected by the lack of job growth found in Meer's study fell roughly in line with the age demographics of minimum wage earners nationally, disproportionately represented by workers between the ages of 18 and 25. About one in six, he says were heads of households. Meer describes these workers as the sort of people, who could benefit from low-wage work and the opportunity to move up the ladder.

Aarinson's work, on the other hand, looked specifically at adults, aiming to establish spending habits for families that depend on at least one minimum wage income for basic expenses. Even within that group, the outsized spending increases brought on by the boost in minimum wage was localized in a very small number of households. Aarinson says that the spending increases he saw in his study were almost entirely due to purchases of new cars in the months following the wage increase.

"It's a very small fraction of households," Aarinson says. "But the amount they are spending on these cars is very high."

Aarinson says that new car purchases have a huge multiplier effect in local economies, because only a fraction of the cost is paid up front. Families who purchased a new car, he says, generally relied on a minimum wage job as a supplementary income and used the extra money from the higher minimum wage to move up the replacement of an older, less reliable car. He also stresses that after the initial provided by a jump in the minimum wage, he would expect the trend to correct itself, as families that made a major investment in a new car struggle to manage the additional debt brought on through the purpose.

"Any time you have an effect like this, it's temporary," says Aarinson. "It's a short-term stimulative effect over the first year or so."

Both Meer and Aarinson come back to the term, "trade-off," as they talk about how their findings might inform the policy debate over whether to raise the federal minimum wage. At it's current level, they agree, a modest increase in the federal minimum wage is not likely to send unemployment levels skyrocketing, nor will it bathe the country's lowest earners in new-found prosperity.

"We could have full employment tomorrow if we decided to ban all farm equipment," says Meer, who says the debate over the minimum wage has been oversimplified, on both sides, to the point that it's now a sort of holy war. "Reasonable people can disagree on the trade-offs."