SINGAPORE  - Formula One enfant terrible Lewis Hamilton is again in the spotlight this week as fevered speculation over his future dominates the build-up to the Singapore Grand Prix.The 27-year-old Briton lies second in the standings behind Ferrari's Fernando Alonso, after a consummate drive in Italy brought his third win of the season and renewed hope of a second world title. Formula One is embarking on a four-stop Asian swing, from Singapore's glittering, skyscraper-studded night race, to Japan, South Korea and India, which may settle this year's unpredictable title race.But the precocious Hamilton's off-track affairs are dominating headlines after he admitted his future was undecided at long-term employer McLaren, and a reported cooling of relations with team-mate Jenson Button.The 2008 world champion brought a sharp rebuke from Button after he tweeted sensitive team information during this month's Belgian Grand Prix. His muted victory celebrations in Italy were widely noted. In the run-up to Singapore, the 14th of 20 races, Hamilton stressed he was "happy with McLaren" -- but said he had not committed to any team next season, when he is out of contract. Mercedes are courting his signature."No, I haven't committed to any team as yet. I don't have a timeline either," Hamilton said, at a promotional event in Mumbai. "I won my first world championship with McLaren and I am happy with their background, the people and environment there," he added. It is the latest in a series of distractions for Hamilton, whose 2011 season was affected by problems with his girlfriend, Pussycat Dolls singer Nicole Scherzinger, and who lost his aunt to cancer last month.The bejewelled driver won on Singapore's "darty", demanding street circuit in 2009, but retired with a puncture in 2010 and finished fifth last year after tangling with Ferrari's Felipe Massa. "For me at the moment, it's just trying to score as many points as I can. We want to win, that's why we exist... but sometimes that's not possible and you have to take what you can," he said on Wednesday."But I think we're in a very strong position this weekend where we can challenge for the win," Hamilton added, describing the Singapore race as "phenomenally tense". "It's one of the most physical because of the temperature outside and the humidity and there's 22 or 24 corners here, and that's a long lap, remembering all the apexes," he said. "And if you make a mistake, there's only barriers -- there's no grass, no gravel. So it's really intense."Alonso meanwhile will look to stretch his 37-point lead over Hamilton -- with Lotus's Kimi Raikkonen and defending champion Sebastian Vettel not far behind -- in a Ferrari car written off at the start of the year as a dud. The softly spoken Alonso has won in Malaysia, his home country Spain, and Germany, and has finished out of the points only once, when he retired in Belgium after a pile-up on the first corner.Vettel, who became Formula One's youngest double champion last year, is struggling in the pursuit of a third straight world title in a Red Bull car whose innovations have been crimped by new technical rules. However Raikkonen has impressed in his return to Formula One from rallying, while Sauber's young Mexican Sergio Perez claimed his second runner-up spot this year in Italy -- fuelling speculation he could replace Massa at Ferrari.