Oddly enough, there is a gang of Republicans who have recently taken up the mantle of poverty. With the exception of Mike Lee, who has proposed to increase the Child Tax Credit, none of the people in this gang has come out with anything remotely interesting or worthwhile. Gang member Marco Rubio recently stepped out of his study, revealing that he had determined the old conservative marriage arguments are still the way to go:
The truth is, the greatest tool to lift children and families from poverty is one that decreases the probability of child poverty by 82 percent. But it isn't a government spending program. It's called marriage.
I have three things to say.
Piling poor people into houses together misses the point.
Matt Yglesias has a good response to Rubio, in which he explains that this marriage point is really about economies of scale and the way we measure poverty in this country. In a one person family, the amount of money it takes to be above the official poverty line is around $11,500. But because it is assumed family members share resources, each additional family member increases the poverty line for that family by less than half that amount. So taking two single people with poverty incomes and putting them in a family together can cause them to come out of poverty even though their incomes have not changed.
This so-called marriage solution is actually just a group living solution. If you can pile enough poverty-income people into one household, that household will eventually be counted as not impoverished. Sharing housing to save money is not a bad idea for those so inclined, but it totally misses the distributive point. If you really think about it, this is a solution to poverty that simply aims to have poor people consume less stuff.
Distributive policy should respond to people's life preferences.
The reality is that marriage rates have fallen pretty much everywhere in the OECD. In fact, the United States has the third highest crude marriage rate of any OECD country.
Countries with lower marriage rates include Finland, Denmark, Sweden, Norway, and plenty of other countries with much lower poverty rates and inequality than the U.S. has. So it's obviously possible for low marriage and low poverty to coincide. Given this possibility, the appropriate role for policy here is to accommodate any secular shifts in preferences for marriage, not to use that shift as an excuse to make people suffer.
Economic insecurity and poverty makes marriage harder.
Determining why poor people choose to forego marriage can be difficult. However, one recent ethnography of working class youth by Jennifer Silva suggests economic insecurity and poverty are big factors.
On first glance, it would seem like adding two poverty-income people to one household through a marriage would be a positive improvement. Indeed, that's what the economies of scale point above is getting at. But this ignores the risk that such an addition entails.
Suppose you are a single person making $9,000 a year and therefore live in poverty. Now suppose you meet someone else making $9,000 and you are considering marrying them. If you marry, the family income goes to $18,000 and is therefore above the poverty line. On a very superficial take, this seems like it would be a real improvement. But that is only if you assume your potential spouse will necessarily remain employed. If they lose their job, you will go from supporting one person with $9,000/yr to supporting two people with $9,000/yr. On the low-end of the labor market, precarity is common and so this is a real risk. Silva's ethnography found poor working class youth making precisely this kind of risk-adverse calculation when considering marriage.
More generally, the point here is that low-income people, because of their economic situation, do not make attractive mates. There is simply too much risk and stress involved in getting married to a low-income spouse. Making low-income people more attractive mates for marriage will require improving their economic situation by providing them more income, more benefits, and providing them greater security against bad outcomes like job loss and wage declines. But these are precisely the left-wing programs those in the GOP (and the DNC for that matter) generally oppose.
Conclusion
The last thing to say on this point is that the marriage argument is really backwards in many ways. Marriage rates have been falling just generally across the world and the US. So you probably cannot blame the overall downward trend in the US on the increase in economic insecurity. However, when we are comparing the economic plight of who is and isn't married, it is entirely fair to say that the relationship largely runs in the opposite direction than people like Rubio suppose. Married people are less impoverished because people who are not impoverished are more likely to get married. Married people are less impoverished because married couples with higher incomes are much less likely to get divorced. With marriage, you have an institution that attracts and retains more economically secure and stable people, not an institution that creates them.