DOWNY LOBELIA (Lobelia puberula)

http://www.discoverlife.org/mp/20p?res=640&see=name&name=Lobelia+puberula&selected=1

more images:
http://www.marylandbiodiversity.com/viewSpecies.php?species=1678

description:
http://www.tropicos.org/Name/5502413?projectid=23
"Lobelia puberula is relatively widespread, and several varieties and forms have been described based on minor components of morphological variation. Steyermark determined the Missouri specimen as var. mineolana E. Wimm., a mostly southern element distinguished by its more or less leaflike bracts and relatively broad calyx lobes. McVaugh (1936) chose to describe these variants as unofficial forms of the species, without resorting to formal taxonomic designations, which seems a sensible approach."

http://vaplantatlas.org/index.php?do=plant&plant=560
"Two geographically correlated varieties, differing in leaf and pubescence characters, were described by Fernald: var. puberula of the Coastal Plain and Piedmont, and var. simulans Fern. of the Appalachians. It is not clear how these putative vars. relate to Virginia material; they are not formally recognized at this time, but are worthy of further study."

Great Blue Lobelia (Lobelia siphilitica L.) is quite different:
http://www.friendsofeloisebutler.org/pages/plants/greatbluelobelia.html

example stigma/stamen tube great blue lobelia:
http://uswildflowers.com/detail.php?SName=Lobelia%20siphilitica
cardinal flower:
http://identifythatplant.com/three-lovely-lobelias/lobelia-cardinalis-2/

great lobelia likes clay soil
https://www.minnesotawildflowers.info/flower/blue-lobelia
... and so, it would appear, does downy lobelia, living as it does in New Castle County, DE.