WA leaders cast their votes in state poll March 9, 2013 - 3:04PM The Liberal and Labor leaders have cast their votes in the West Australian election, with Premier Colin Barnett playing down polling that points to a landslide win for his Liberal party. A Newspoll released on Friday night showed the incumbents would win 59.5 per cent of the vote on a two-party preferred basis. Mr Barnett maintained that at least a dozen seats hung in the balance. "I can honestly tell you I don't know who's going to win those seats," he told reporters at a polling booth in Cottesloe, in his affluent western suburbs electorate, where he cast his vote. There's going to be a very close contest. I hope I can continue and I hope we get the chance to finish many of the projects around the state, around the city, and carry on. Labor leader Mark McGowan was first off the mark in casting his vote in the working-class satellite suburb of Rockingham, south of Perth. Mr McGowan, who had also kicked off the party's official election campaign 10 days ahead of his opponent, arrived in his trademark red campaign bus. He remained optimistic despite the polling, saying he'd wait and see what happened. He said he would spend the day visiting polling booths around the city. Deputy federal opposition leader Julie Bishop was full of praise for Mr Barnett, saying he would continue to stand up for the state's interests. Ms Bishop said Mr McGowan had tried to distance himself from federal Labor, but that was futile because there was a deep distrust of the Gillard government that the state party couldn't shake. Polls close at 6pm WST.