I attended a poorly ranked school for my undergraduate education. Will this affect my chances for a PhD in economics?

As the commenters have pointed out, a lot will depend on your ability to get good letters of recommendation. However, there is an important issue to note: a good letter of recommendation does not mean the same thing as "a letter from someone famous." You can get a letter of recommendation from a big name that is completely useless, if it doesn't provide any real information of value about the candidate.

Instead, what you want are people who can testify that you are a good student, and show evidence that you can become a good researcher. Since you have excellent records, and are working with a research group before applying to graduate school, I think you have the right groundwork for getting good letters. To make sure that you do so, you'll want to meet with the people who will be writing the letters, make sure that they are willing and enthusiastic about writing the letters (hint: if they are at all hesitant, do not get a letter from them!), and then provide them with the necessary material they'll need (CV's, samples of writing and research work, citations and awards, etc.) to write the letter.

Ultimately, the only way attending an unranked school will affect your chances of getting in as a graduate student is if the admissions committee at the school you're applying to shows such a bias. If you're concerned about such a possibility, and have the resources (time, money, motivation) to do so, setting up a meeting with the person in charge of graduate admissions at the department you're interested in probably can't hurt.

It will probably affect your chances. But it's not a show-stopper.

Coming from a top school means students are more likely to get that second look and it means that students are more likely to have recommendations from people than the folks on the admission committee already know and trust. For those reasons, coming from a top school affords a real advantage over unranked schools. It's not fair but there are lots of reasons to believe that an applicant from a top school will get more bites than an identical one from an unranked school.

That said, if you think you can put together a solid application, you shouldn't get too hung up about the status symbols you won't have and others might. Nobody is making decisions based only on where the applicant went to college.

If you have great test scores, a history of excellent academic performance (sounds like you do), a demonstrated ability to do solid research, and a glowing set of letters from a good set of letter writers, you have a good chance at a top program. Focus on the things you can change, improve, and build on and not on the stuff you can't.

FWIW: I did my undergrad at an unranked liberal arts college and graduate school at a top school — although not in economics. Moving up the status hierarchy is always harder than lateral or downward moves, but it happens all the time.

I have been in your situation several years ago (in 2011). I graduated BA in Economics and Business Adminsitration from anranked university from one of the developing countries in Eastern Europe. But then I enrolled in Master's Program where I had a chance to meet highly respected Economists who were professors in US programs as well. Neither my Master's Program was ranked. They were just funded by the World Bank and had enough money to invite US professors. By getting As and A-s in all of their courses and being engaged with the professors I earned quite good reputation and showed them that I was motivated and knowledgeable enough to study in some 30-40 US programs. Despite the fact that my school was not ranked after getting recommendation letters from these well-known US professors I was admitted in top 30 programs in the US.

The take away from my story is that the rank of the university does not as far as you get strong recommendation letters from well-known and well-published economists, researchers.