(CNN) -- Is America's honeymoon with Sarah Palin over? Polls suggest that might be so.
Palin appears to be losing some of her initial appeal as Democrats make gains in the polls.
The Alaska governor came out swinging at the Republican National Convention, energizing her party's base and shifting the momentum to John McCain's favor.
At rallies in the week following the convention, the McCain-Palin duo saw their best attendance and a newfound zeal, and the Republican ticket took the lead in national polls for the first time.
But polls show the momentum has shifted once again.
Palin's favorable rating is at 40 percent, according to a CBS News/New York Times poll. That's down 4 points from last week. Her unfavorable rating is at 30 percent, rising eight points in a week.
The poll was conducted September 12-16 and has a sampling error of plus or minus three percentage points.
Former Bush adviser Karl Rove predicted Wednesday that Palin's star power would wear off.
"Nothing lasts for 60-some-odd days," Rove told The Associated Press. "Will she be the center of attention in the remaining 48 days? No, but she came on in a very powerful way and has given a sense of urgency to the McCain campaign that's pretty remarkable."
But this week, the Democrats recaptured the headlines and Obama regained his lead in the national polls.
CNN's latest poll of polls, out Thursday afternoon, shows him ahead of McCain by two points, 47-44 percent.
The poll of polls consists of six recent surveys: CBS/NYT (September 12-16), Quinnipiac (September 11-16), IPSOS-McClatchy (September 11-15), Gallup (September 15-17), Diageo/Hotline (September 14-16) and American Research Group (September 13-15). It does not have a sampling error.
After a week in which McCain put Obama on the defensive over allegations of playing the gender card, the economic crisis has given Obama an opportunity to go on the offense. Most Americans see Obama as more capable than John McCain when it comes to handling the economy, polls show.
The Illinois senator has been aggressively attacking what he sees as shortcomings in McCain's economic plans.
Also this week, McCain handed Obama ammunition for what has turned out to be a weeklong attack.
Despite the shake up on Wall Street, McCain said Monday that "the fundamentals of the American economy are strong."
The Obama campaign jumped on those remarks, replaying them in a campaign ad, even after McCain clarified his comments. He said what he meant was that American workers are the fundamental strength of the economy and that the country will rebound with their help.
Obama continued to criticize the remark Wednesday at an event in Elko, Nevada: "His campaign must have realized that probably wasn't a smart thing to say on the day of a financial meltdown, so they sent him back out a few hours later to clean up his remarks."
Obama has filled this week's campaign speeches with a focused view of his economic agenda and sound-bite friendly slams to bruise McCain's image.
"This is somebody who has been in Congress for 26 years, who put seven of the most powerful Washington lobbyists in charge of his campaign. And now he tells us that he is the one who is going to take on the old boys' network. The old boys network, in the McCain campaign, that's called a staff meeting," he said Wednesday.
David Gergen, a senior political analyst for CNN and former presidential adviser, said neither candidate has shown expertise on the economic situation, but Obama has gained more from it than McCain.
"The momentum for John McCain and Sarah Palin has stalled out. There is a little momentum on Barack Obama's part. But he hasn't yet fully seized it and it is still very close," he said, adding that McCain could still recapture it.
But the Democratic ticket has shown a weakness in regards to the government takeover of insurance giant AIG.
A day after saying the federal government should not come to the rescue of AIG, Democratic vice presidential candidate Joe Biden shifted his position Wednesday, saying he needs to get more details on the terms of the $85 billion takeover.
"The truth is I don't know what the bailout is yet," Biden said Wednesday afternoon in Maysfield, Ohio.
Obama was slow to respond when asked about the AIG deal. A statement issued from his campaign did not clarify whether he supports or opposes it.
McCain said he didn't want the government to have to take over the company, but it was necessary.
"When AIG was bailed out, I didn't like it, but I understood it needed to be done to protect hard working Americans with insurance policies and annuities. Sen. Obama didn't take a position. On the biggest issue of the day, he didn't know what to think. He may not realize it, but you don't get to vote present as president of the United States," he said Thursday in Cedar Rapids, Iowa.
He also accused Obama of seeing the economic crisis as a "political opportunity."
Obama's campaign responded by accusing McCain of flip-flopping on the issue because he said he opposed the bailout earlier this week.
"Barack Obama does not second guess the Fed's decision to take unprecedented action to prevent the failure of one of the largest insurance companies in the world from creating an even larger crisis, and he believes it must protect families who count on insurance," said campaign spokesman Bill Burton.
As the McCain campaign tries to regain its footing, they're hitting hard with a new ad accusing Obama of wasting taxpayers money.
The ad says Obama's economic policies would severely worsen the country's economic woes.
"When our economy's in crisis, a big government casts a big shadow on us all," the ad's narrator states. "Obama and his liberal Congressional allies want a massive government, billions in spending increases, wasteful pork. And, we would pay -- painful income taxes, skyrocketing taxes on life savings, electricity and home heating oil." "
Obama has repeatedly said the notion he will raise taxes on middle-class Americans is untrue.
According to a CNN fact check, Obama's tax plan would increase taxes in 2009 on the wealthiest 20 percent of households, while offering tax cuts for the other 80 percent. The largest increases would be on the top 1 percent of earners, according to analysis by the Tax Policy Center, a nonpartisan research group whose staff of experts includes former economic advisers to the White House and Congress under both Republicans and Democrats.
By comparison, the Tax Policy Center analysis says McCain would offer tax cuts across the board. Those at the top end of the scale would get the biggest percentage cuts under McCain, while households with the lowest incomes would receive the largest percentage cuts under Obama's plan.
