Cinci is an easy place for quick connections. One option you overlooked is LGA. Take the ORD-LGA shuttle (w/ free beer and wine in coach!) and connect to the LGA-DCA shuttle (w/ more free beer and wine in coach!). The Marine Air Terminal at LGA is super easy for connections...and if you happen to miss one flight, there will be another one an hour later. Only thing will be extra steps necessary to book ORD-DCA via LGA (which I think will be a broken fare).