Answer: swingvote

AnswerCrossword Clue
SWINGVOTESought-after election bloc
SWINGVOTEMake-or-break election bloc
SWINGVOTEFigure in a 5-4 Supreme Court decision
SWINGVOTETarget for many a political ad
SWINGVOTEElection decider, perhaps