By John Whitesides, Political Correspondent
WASHINGTON (Reuters) - After a difficult week that sparkedDemocratic worries, Barack Obama fired back at Republicanpresidential rival John McCain on Friday with tough ads and aretooled message outlining their differences on taxes.
Obama acknowledged the concerns of his supporters after aweek dominated by McCain and his new running mate, Alaska Gov.Sarah Palin, who charged out of the Republican convention on awave of momentum and unleashed a volley of harsh personalattacks against him.
The emergence of Palin, an anti-abortion and pro-gunconservative who electrified the party's base supporters,seemed to knock Obama off stride and propelled the Republicansinto a slight lead in the November 4 election race in a flurryof national opinion polls.
But Obama and his campaign had a clear message to nervoussupporters on Friday: Calm down.
"People start worrying. Here's what I can guarantee you --we are going to be hitting back hard," he said at a rally inDover, New Hampshire, where he spelled out his plan to cuttaxes for most workers and said he would provide three timesmore tax relief for middle-class families than McCain.
Obama's campaign released three ads hitting McCain as anout-of-touch supporter of President George W. Bush who would beunable to deliver economic improvements or on his promise tochange the culture in Washington.
"Things have changed in the last 26 years. But McCainhasn't," one of Obama's new ads says. "He admits he stilldoesn't know how to use a computer, can't send an e-mail. Stilldoesn't understand the economy."
In another ad, Obama talks directly into the camera toexplain his promise of change. "Because this year, change hasto be more than a slogan," he said.
Obama campaign manager David Plouffe released a memo sayingMcCain had shown he was "willing to go into the gutter" to winthe election.
"Today is the first day of the rest of the campaign," hesaid, promising to respond with "speed and ferocity" toMcCain's attacks.
"His campaign has become nothing but a series of smears,lies, and cynical attempts to distract from the issues,"Plouffe said of McCain. "As Barack Obama said earlier this week'enough is enough.'"
MCCAIN WITH HIS OWN ATTACK
The McCain campaign issued its own attack on Obama. "He wasthe world's biggest celebrity, but his star's fading. So theylashed out at Sarah Palin," the narrator says in a new ad. "Howdisrespectful."
The McCain camp said the new approach from Obama wasdesigned to hide his lack of achievement.
"What is becoming clear to the American people is the factthat Barack Obama has no record of bipartisan legislativeaccomplishment, no history of bucking his party and no chanceof bringing change," said McCain spokesman Tucker Bounds.
The political firestorm caused by McCain's pick of thevirtually unknown Palin as his No. 2 and the biting attacks onObama by Republicans had drowned the Illinois senator'seconomic message in the last week. Democratic strategists haveworried he seemed uncertain how to respond.
McCain, a four-term Arizona senator, and Palin latched onto Obama's message of change and presented themselves as thetrue reformers in the race -- a move that seemed to catchObama's team off guard.
Some Democratic activists also questioned why Obama wasleft to handle the responses to McCain and Palin's attacks andurged a more active role for his No. 2, Delaware Sen. JoeBiden, and surrogates in attacking the Republicans.
The growing sense of Democratic nervousness was palpableamong grassroots activists and elected officials, forcing Obamato ease their concerns.
In New Hampshire, he said Republicans attack Democraticpresidential candidates with lies every four years and citedwhat he described as an old saying from former PresidentAbraham Lincoln.
"He said, 'If you don't stop lying about me, I'm going tohave to start telling the truth about you.' That's what we'regoing to do," he said. "Our focus is on tax policy. John McCainleaves 100 million people out. I lower taxes. He doesn't."
In a conference call, Democratic Sen. Richard Durbin ofIllinois criticized McCain for saying at a forum in New York onThursday that it was easy for him to be "somewhat divorced"from everyday economic challenges of people.
"That evidences why he really isn't going to bring change,"Durbin told reporters.
(Additional reporting by Caren Bohan; Editing by JackieFrank)
