CHICAGO – The jockeying to replace Jesse Jackson Jr. began before the ink was dry on the former congressman's resignation letter.

Among those expressing an interest: Chicago aldermen, a former NFL linebacker and a defense attorney who represented R&B singer R. Kelly and former Gov. Rod Blagojevich.

But as the field of would-be successors grows to a dozen or more names – one of whom may be another member of the Jackson family – party leaders and political analysts say a stampede of candidates could pose risks for the Democratic stronghold. Spread the field of candidates too thin, they say, and it becomes easier for a more conservative candidate – or anyone else party leaders don't want – to pull off a win.