US senate candidate Mark Warner took himself out of the running as a potential vice-presidential candidate this year, telling about 2,000 delegates at the state Democratic convention that he will say no if Barack Obama offers him a spot on the ticket.With Democrats saying that Virginia could be key to Obama’s hopes of winning the presidency, the Obama campaign is reportedly considering Warner, Timothy Kaine and James Webb as possible vice-presidential contenders.But in his speech here to officially accept the Democratic nomination for Senate, Warner said he is “110 per cent committed” to his race against former governor James Gilmore III, the GOP nominee.“Let me be clear about this: I have been working very hard these last few months to ask the people of Virginia to give me the honor of being their US senator,” Warner said. “I will not seek, and I will not accept, any other opportunity.” Warner’s speech capped a day-long event during which Kaine, Webb and other party leaders urged Virginia Democrats to unite behind Obama.Virginia last voted Democratic in a presidential election in 1964, but Obama has said he can turn the state blue this year in his race against John McCain, the presumptive GOP nominee.