single shot
n.— «Other things which play havoc with aldermen candidates is many voters do not vote for five aldermen. The under votes in the aldermen election are substantial. So it is important for the candidate to be the first, second or third choice of the voter. Another little known and rarely used tactic by some candidates is to quietly urge their supporters to just vote for them and no other alderman candidate. This ensures no other candidate is receiving votes from their supporters and as long as they are the second or third choice of the other voters, their odds of winning are increased significantly. This tactic, also known as “single shot” is rarely used for if it became public knowledge, it would backfire against the candidate.» —“Crowded Aldermen Field in City of Frederick, MD Election” by George Wenschhof Air-it-Out with George Wenschhof July 9, 2009. (source: Double-Tongued Dictionary)
(More commonly known as “bullet voting.”)