I either read on their website or heard on one of the webinars that Boren doesn't have country quotas like some other fellowships, like Fulbright. So, the number of awards for a given country is based on applicants' interest in that country in a given year. That being said, their website also says that the regional committees forward a set number of applications for their region onto the national committee... I wouldn't say you're competing with other applicants in your chosen country, but perhaps in a sense with other applicants for your region during the application review by the regional committee. If you've made it onto the national review committee (and let's hope the dates email indicates that), my guess is that you'd be competing at that point with the portion of the general applicant pool that also made it to nationals. Fingers crossed!
p.s. Total tangent, but when as I wrote "nationals," I couldn't help but think of this...