US STOCKS-S&P 500 futures fall as Brexit vote count shows tight race
* S&P 500 futures down after Sunderland results
* Opinion poll puts "remain" campaign in lead
* Banks climb after Fed gives passing grade in stress tests
* Indexes up: Dow 1.3 pct, S&P 1.3 pct, Nasdaq 1.6 pct (Adds detail on futures, bank shares, comment)
By Noel Randewich
June 23 (Reuters) - U.S. stock index futures fell in after-hours trading on Thursday after vote counts showed a tight race in Britain's referendum over whether to stay in the European Union.
S&P E-mini futures fell 0.15 percent after the vote count in the northeastern city of Sunderland showed a stronger-than-expected vote in favor of taking Britain out of the European Union.
Sterling fell as low as $1.4351 against the dollar, more than wiping out all its gains that had lifted it above $1.50 for the first time this year on the back of an earlier YouGov opinion poll that suggested Britons had voted 52-48 percent to stay in the EU.
Earlier on Thursday, U.S. investors bet the United Kingdom would remain part of the European Union, potentially avoiding damage to European trade and its consequences for the global economy. Continuación...