This is pretty incredible when you think back to a year ago and the difference was 23% in favor of Obama.

Americans are divided over whether President Barack Obama or his predecessor has performed better in the White House, according to a new national poll.

And a CNN/Opinion Research Corporation survey released Friday also indicates in the battle for Congress, Republicans hold large advantages over the Democrats among independents, men and blue-collar whites. The poll also indicates that Republicans are much more enthusiastic than Democrats to vote.

By 47 to 45 percent, Americans say Obama is a better president than George W. Bush. But that two point margin is down from a 23 point advantage one year ago.

"Democrats may want to think twice about bringing up former President George W. Bush's name while campaigning this year," says CNN Polling Director Keating Holland.

The loss of independents by Obama and the Democrats is catastrophic.

According to the poll, 45 percent of the public approves of the job Obama's doing as president, up three points from late last month, with 52 percent disapproving. Fifty-nine percent of independents disapprove of how the Obama's handling his duties, with 37 percent giving him a thumbs up.

In the fight for control of Congress, 52 percent of likely voters say they would vote for the generic Republican candidate in their district if the election were held today, with 45 percent saying they would back the Democrat. The Republican's seven point margin is down from a nine point advantage late last month.

Note that the GOP is over 50% on the generic ballot. Also note that only 37% of indies think Obama is doing a good job. That's a 17 point drop from the 54% of independents that supported him on election day.

The "Blame Bush" mantra is nearly dead. It may work with left leaning independents and other Democratic constituency groups. But it is hardly the kind of rallying cry that will move people to the polls on election day.