Delaware is really a mess. Their voting district lines only occasionally correspond to city / township boundaries.
I tried the math on Hockessin. In those six voting districts that fully fall within the township boundaries, or only include a minor part of a neighbouring township, Romney won 3071:3060. There are, however, three more voting districts that cover a relevant portion of Hockessin, but also of neighbouring townships. They went 1884:1756 Obama. The total of all districts that include parts of Hockessin is 4944:4877 Obama.
Looking at the above figures, I would say that there is a slight chance that Rpmney won Hockessin, bot it is more likely to have narrowly gone to Obama.
If you can post a list of other towns / townships that you haven't checked yet, and of which you think they may have gone to Romney, I can over the next days do some more number-crunching.
Results by voting district are published here (I had problems with their download function, had to copy and paste date from the html results page):
http://elections.delaware.gov/results/html/unofresl.shtmlThe precinct maps for New Castle County are here (the 2012-2022 version applies to the General election):
http://electionsncc.delaware.gov/senate/senate.shtml