The word "progressive" means that I align myself with progressive goals. For example, I wouldn't disagree with much of anything on this list of Senator Bernie Sanders' positions (although I definitely think that marijuana should be legalized and I'd add some things to his priorities - like criminal justice reform and gun control).
But the word "pragmatic" indicates that I think the process we use to reach those goals is as important as identifying what they are. As Dr. Martin Luther King, Jr. said, "So I have tried to make it clear that it is wrong to use immoral means to attain moral ends." I am not going to assume that I know what Dr. King would describe as "immoral means," but I'll give you some ideas about my own thoughts.
One way that plays out is in "not letting the perfect be the enemy of the good." To illustrate, I share Sen. Sanders' belief that single payer health insurance is the ideal. But it was Sanders himself who pointed out that, at the time Obamacare was passed, there were perhaps 8 votes in favor of single payer in the Senate. Meanwhile, people were literally dying for lack of health insurance and medical bills were the single most frequent contributor to bankruptcy. To wait until there were 60 votes in the Senate for single payer would have been to ignore the very real and present needs of people in this country. Crafting Obamacare and getting the 60 votes it needed to pass was the pragmatic thing to do precisely because it was doable and a significant improvement on the status quo. That's why, in the end, Senator Sanders voted for it.
But being a pragmatist also means paying attention to the potential for collateral damage in implementing your goals. On the issue of single payer, that was most recently demonstrated by Vermont's failure to implement such a system. They found that it would require an 11.5% income tax on all residents. An abrupt change from our current system would create big winners and losers and the unintended consequences on the latter turned out to be too much to ask. As an alternative, a pragmatist would celebrate the movement away from employer-based health insurance created by the exchanges in Obamacare as a step towards single payer - minus the unintended consequences. That's also what it means to play the long game.
If there is a patron saint of pragmatists, it would be Reinhold Niebuhr. He is the Christian theologian most commonly known for the idea that we have to live in the world as it is, not as we want it to be. That means that getting involved in social change means getting your hands dirty. Purity in pursuit of goals is not an option. Here's how Wilfred M. McClay described it:
Niebuhr dismissed as mere “sentimentality” the progressive hope that the wages of individual sin could be overcome through intelligent social reform, and that America could be transformed in time into a loving fellowship of like-minded comrades, holding hands around the national campfire. Instead, the pursuit of good ends in the arena of national and international politics had to take full and realistic account of the unloveliness of human nature, and the unlovely nature of power. Christians who claimed to want to do good in those arenas had to be willing to get their hands soiled, for existing social relations were held together by coercion, and only counter-coercion could change them. All else was pretense and pipedreams.That might seem at odds with the idea of avoiding unintended consequences. But it's really all of one piece. Pragmatists acknowledge that there will be collateral damages, and they chose their means carefully to limit them. In the case of the ACA as health care reform, that meant - to a certain degree - getting your hands dirty by getting in bed with health insurance and pharmaceutical companies. The whole approach by the Obama administration of incentivizing reform in those kinds of institutions rather than mandating it is a way to limit the backlash that leads to unintended consequences. That's what it means to live in the world as it is.
Of course, there are potential pitfalls for the pragmatic progressive. The most significant is that there are times that the line between getting your hands dirty and co-optation of your goals becomes very narrow. As the saying goes, "lie down with the dog, get up with the fleas." That's why we so often hear President Obama (a true pragmatist) talk about the importance of his North Star. In order to avoid that possibility, it's important for the pragmatist to "keep their eye on the prize."