Tim Bowen really hits the nail on the head with his discussion of the collocates of this versatile word.
Politicians often hit the campaign trail as they attempt to win votes in elections. Most observers believe that successful candidates hit the ground running (are successful from the very start) hitting the target with a lot of comments and policy statements, while less successful candidates may hit a bad patch (reach a difficult stage), hit a few problems and have to concede defeat. Some commentators seem to hit the nail on the head (speak the exact truth) when they describe candidates and this story often hits the headlines (is the main story in the newspapers), although the candidate themself may hit the roof (became very angry) whenever anyone suggests this was the case.
Away from the world of politics, ordinary mortals hit the road when they leave on a long journey, hit the shops when they go out for a day’s shopping, hit the town when they go out for the evening, and hit the sack when they go to bed. When you are hungry a tasty meal will often hit the spot (be exactly what you need) but when you are thirsty be careful you don’t hit the bottle (drink alcohol to excess) or you may end up hitting rock bottom (reaching the lowest possible level) and you may not know what hit you (be extremely shocked or surprised). Be patient, keep trying and, who knows, in the end you might hit the big time (become very successful).