Words to Describe challengers

How challengers often is described ("________ challengers")

• regional
• congressional
• principal
• unsuccessful
• top
• successful
• prospective
• chief
• most
• political
• party
• credible
• revolutionary
• promising
• liberal
• potential
• democratic
• ethnic
• strong
• viable
• primary
• experienced
• outside
• fewer
• wing
• formidable
• unknown
• few
• main
• minor
• black
• internal
• serious
• ideological
• aggressive
• worthy
• vigorous
• stronger
• presidential
• competitive
• electoral
• senate
• new
• strongest
• domestic
• younger
• funded
• global
• republican
• financed
• effective
• possible
• male
• likely
• female
• powerful
• future
• independent
• weak
• quality
• communist
• other
• major
• conservative
• radical
• external
• previous
• multiple
• nearest