Republicans seeking to change the national conversation about the presidential race have embarked on a concerted effort to tarnish Sen. Barack Obama's character and credibility as national and battleground state polls show him opening a lead on GOP opponent Sen. John McCain.

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"It's a dangerous road, but we have no choice," a top McCain strategist told the New York Daily News. "If we keep talking about the economic crisis, we're going to lose."

The latest nationwide Rasmussen poll shows Obama with a 52-44 percent lead over McCain. A George Washington University poll gave Obama a 50-43 percent edge. And the latest Gallup survey shows Obama leading 50-44 percent. The GOP ticket is also trailing in states that until a few weeks ago were considered battlegrounds. (Watch Video)

GOP vice presidential nominee Sarah Palin kicked off the assault over the weekend saying Obama sees America as so imperfect "that he's palling around with terrorists who would target their own country."

She said she was referring to university professor William Ayers, once a member of the 1960s radical group the Weather Underground, which has been blamed for several bombings when Obama was a child. It appears that Ayers' strongest tie to Obama appears to be a 1995 meet-the-candidate event he hosted early in Obama's political career.

On Monday, she was introduced at a rally where Obama's name and the terrorism line were offered by surrogates. A Florida sherrif introduced Palin to a supportive crowd by refering to the Democratic presidential nominee as "Barack Hussein Obama."

After offering vocal support of Palin, Lee County Sheriff Mike Scott used Obama's middle name and the crowd roared its approval. CBS News reported that after Scott left the podium, a local radio host named Mandy Connell took the stage and drew a loud ovation when she said Obama "hangs around with terrorists."

Palin claims that Obama's association with Ayers "hasn't been talked about." However, Obama was questioned about Ayers during a prime-time Democratic debate against Sen. Hillary Rodham Clinton before April's Pennsylvania primary. He has denounced Ayers' radical views publicly. And a New York Times article published Saturday quoted Obama saying that Ayers was "somebody who engaged in detestable acts 40 years ago, when I was 8."

Regardless, Palin said of Obama on Saturday that "this is not a man who sees America like you and I see America."

In an interview in The New York Times published Monday, Palin spoke about Obama's relationship with the Rev. Jeremiah Wright, who made anti-American comments even though John McCain had said talk of Wright was off-limits.

"I don't know why that association [with the Rev. Jeremiah Wright] isn't discussed more, because those were appalling things that that pastor had said about our great country," she said in an interview with Times opinion columnist William Kristol, a McCain supporter.

Obama began addressing the Wright issue during the primary season, when opponents began circulating video clips of incendiary sermons delivered by Wright at his Chicago church.

Wright officiated at Obama's wedding, baptized the Obamas’ children, and prayed with the family before Obama officially announced his candidacy for president.

The debate stirred by the video clips culminated with Obama delivering a speech on March 18 in which he explained his 20-year association with the minister, who later stepped down as leader of Trinity United Church of Christ. In the speech, Obama also repudiated Wright's comments. (Speech Audio | Transcript)

"I have already condemned, in unequivocal terms, the statements of Rev. Wright that have caused such controversy. For some, nagging questions remain," Obama said. "Did I know him to be an occasionally fierce critic of American domestic and foreign policy? Of course. Did I ever hear him make remarks that could be considered controversial while I sat in church? Yes. Did I strongly disagree with many of his political views? Absolutely -- just as I'm sure many of you have heard remarks from your pastors, priests, or rabbis with which you strongly disagreed.

"But the remarks that have caused this recent firestorm weren't simply controversial. They weren't simply a religious leader's effort to speak out against perceived injustice. Instead, they expressed a profoundly distorted view of this country -- a view that sees white racism as endemic, and that elevates what is wrong with America above all that we know is right with America; a view that sees the conflicts in the Middle East as rooted primarily in the actions of stalwart allies like Israel, instead of emanating from the perverse and hateful ideologies of radical Islam."

Obama fired back at McCain on Sunday saying, "McCain's campaign has announced that they plan to turn the page on the discussion about our economy and spend the final weeks of this campaign launching Swiftboat-style attacks on me.

"Think about that for a second. Turn the page on the economy? We're facing the worst economic crisis since the Great Depression, and John McCain wants us to 'turn the page?' Well, I know the policies he's supported these past eight years and wants to continue are pretty hard to defend. I can understand why Senator McCain would want to 'turn the page' and ignore this economy."

Also on Sunday, Obama also unveiled a TV ad on the economy that describes McCain was "erratic in a crisis." Some see that as a reminder of McCain's age, 72.

And on Monday, his campaign released a Web video "documentary" about McCain's involvement with convicted thrift owner Charles Keating. The ad "is a window into McCain's economic past, present and future," a campaighn spokesman said.

Rep. Rahm Emanuel, a Chicago Democrat and Obama supporter, warned against McCain's strategy on CNN's "Late Edition" Sunday.

"If we are going to go down this road -- you know, Barack Obama was 8 years old, somehow responsible for Bill Ayers," he said. "At 58, John McCain was associating with Charles Keating."

Just months into his Senate career, in the late 1980s, McCain participated in meetings with banking regulators on behalf of Keating, a friend, campaign contributor and S&L financier who was later convicted of securities fraud.

The Senate Ethics Committee investigated five senators' relationships with Keating. It cited McCain for a lesser role than the others, but faulted his "poor judgment."

Obama campaign manager David Plouffe said in a statement, "McCain's Keating history is relevant and voters deserve to know the facts."

Meanwhile, seven aides to Palin have reversed course and agreed to testify in an investigation into whether the Republican vice presidential nominee abused her powers by firing a commissioner who refused to dismiss her former brother-in-law.

The independent investigator conducting the probe plans to turn over his conclusions on the case by next Friday to the Legislative Council, the body that authorized it.

Alaska's Supreme Court, meanwhile, is considering a Republican request to block the findings of the legislative inquiry. The high court scheduled arguments for Wednesday over whether the case is being manipulated to hurt Palin before Election Day on Nov. 4.

The case began before McCain asked her to be his running mate.