A base hit on which the batter scores a run. Synonym:homer.
2.
Something that exactly succeeds in achieving its goal. Synonyms:bell ringer, bull's eye, mark."Scored a bull's eye" , "Hit the mark" , "The president's speech was a home run"
... Wilson's was, to use a baseball phrase, a home run for the Democratic side. They were delivered without much preparation and were purely extemporaneous in character. The Republican opposition soon began to wince under the smashing blows delivered by the Democratic candidate, and outward proof was soon given of the fear and despair ... — Woodrow Wilson as I Know Him • Joseph P. Tumulty