McCain aims to slow Obama momentum in debate

By John Whitesides, Political Correspondent

NASHVILLE (Reuters) - Republican John McCain hopes to halt Democrat Barack Obama's momentum and gain new life in the White House race on Tuesday when the presidential rivals meet in their second debate.

With less than a month until the November 4 election, the face-to-face debate offers McCain one of his last and best chances to recast a presidential race that has been turning towards Obama in the last few weeks.

"McCain has a big opportunity with this debate," said Peter Brown, assistant director of the Quinnipiac University poll. "He has to change the dynamic and make people re-evaluate Obama."

Obama has solidified his national lead and gained an edge in crucial battleground states as the Wall Street crisis has focussed the attention of voters on the economy, an area where polls show voters prefer the Illinois senator's leadership.

A Reuters/C-SPAN/Zogby poll released on Tuesday gave Obama a 3-point edge on McCain, an Arizona senator, but other polls have shown an even bigger margin for Obama.

The economic turmoil continued on Monday, when stocks tumbled on Wall Street in a sign the $700 billion (400 billion pound) government bailout of U.S. financial concerns did not ease public concerns about the economy.

McCain's campaign has unleashed a volley of attacks on Obama in the last few days as his advisers signalled they wanted to turn the debate away from the economy.

McCain and running mate Sarah Palin have tried to turn the campaign focus back to Obama and his associations with figures like former 1960s radical William Ayers and his former minister, the Rev. Jeremiah Wright.