I waited almost two hours to vote today in Mt. Pleasant, my neighborhood in D.C. Andrew, our web editor, lives one neighborhood over in Columbia Heights, but waited only about five minutes. Why did I have to wait while he breezed through?

I arrived at my polling place at 9:35 a.m. I waited in a line that snaked out the door, around the perimeter of a small parking lot, and down the block. I finally voted and walked out the door at 11:20 a.m. Andrew walked into his polling place shortly before I started waiting, got his ballot, voted, and left. It took five minutes, tops.

One definite difference between our two polling places: My precinct has more than twice as many voters registered as Andrew’s (4,839 vs. 2,117). My list was divided into six check-in stations, as opposed to the four at his polling place, which means about 800 people could pass through each check-in station at my polling place, while about 500 would go through each line at Andrew’s. But is that enough of a difference to account for my wait?

One of the big roadblocks to understanding Election Day problems like long lines at polling places is that there aren’t always that much data to look at. Back in April, two graduate students at the University of California, Berkeley, released one of the only academic studies of polling place lines ever. Their work is “the first systematic attempt to determine how common lines are,” they wrote, but their report mostly looked at data collection methods, not the root causes of lines.

After the eight-hour waits to vote in Ohio during the 2004 election, some critics were quick to point to the lines as evidence of voter suppression. Perhaps. But it’s unlikely that some political operative was trying to suppress my vote and not Andrew’s, as there’s no question that Obama will claim D.C.’s three electoral votes. (Thank you, 23rd Amendment!) Both of our neighborhoods are in the same ZIP code and have demographically similar populations.

And yet, because of this morning’s long line, some voters in my precinct probably were dissuaded from casting a ballot. There were people waiting in line who were vocally anxious about running late for work, while others with similar concerns probably didn’t get in line to begin with. Even without intentional election manipulation, it seems clear that there are inefficiencies in our election systems that make it easier for some people to vote than others.