This is the fifth election UKIP have thought so not exactly a young party.
Our voting system does not favour small extreme parties (right or left), so UKIP will get a single figure number of MPs. Probably not enough to prop up a Conservative Party without a majority.
UKIP are supported by a small minority of mainly Euro Skeptic Tories, exercising their protest vote. They won't get anywhere, and if Farage fails to get elected and resigns as he has promised to, they will implode after 5th May.