Israel's Prime Minister Benjamin Netanyahu is fighting to hold on to power, as voters go to the polls in one of its closest election races in years. He called the snap election after failing to form a governing coalition in the wake of an election in April. Polls forecast his right-wing Likud party to tie with its main challenger, the centrist Blue and White party led by former military chief Benny Gantz. Smaller parties could therefore have a big say in the final outcome. Negotiations on the formation of a new coalition are expected to start as soon as voting ends at 22:00 (19:00 GMT) and exit polls are published. What happened last time?Likud and Blue and White came away with 35 seats each in the 120-seat Knesset. Mr Netanyahu declared victory and it appeared that he would be able to secure a majority with the backing of smaller right-wing and religious parties. But after several chaotic weeks the attempted coalition-building collapsed into recriminations. On the surface was a dispute over Israel's secular versus its religious character, says the BBC's Tom Bateman in Jerusalem. But ultimately, our correspondent adds, Mr Netanyahu's problems stemmed from a narrowing range of options to build a governing bloc, weakened as he is by the charges of bribery, fraud and breach of trust he faces in three corruption cases, pending a final hearing. Mr Netanyahu has denied any wrongdoing. He refuses to rule out seeking parliamentary immunity should he stay in power.