Democrats may be cheered by the fact that President Bush’s approval ratings are at their lowest point in his presidency and that his re-elect numbers aren’t great. But they have to be worried about a pro-Republican shift in voters’ party identification. [IMGCAP(1)]

It may not seem dangerous that, according to a new Pew Research Center poll, 31 percent of registered voters regard themselves as Democrats, 30 percent as Republicans and 39 percent Independents, but that’s a 5-point GOP switch from the average from 1997 to 2000.

During that period, 33 percent considered themselves Democrats and 27 percent Republicans. According to Pew, the GOP has gained among every demographic group except African-Americans — including 8 points among Hispanics.

Even more significantly for 2004, Republican ID gains have been substantial in “light red” or “light blue” swing states carried narrowly by either Bush or Vice President Al Gore in 2000.

Republicans made gains in every one of the seven swing states that Gore carried with 51 percent of the vote or less, which together account for 77 electoral votes. Bush won the election, of course, with 271 electoral votes to Gore’s 266.

In Iowa, for example, which Gore carried by a bare 4,110 votes, party ID among registered voters has switched from 32 percent Democratic and 27 percent Republican to 34 percent to 27 percent in favor of Republicans.

In Michigan, with 17 electoral votes, Republicans have gained 8 points, according to Pew. In Wisconsin, which Gore won by a margin of just 5,396, party ID has moved 5 points toward the GOP.

In Pennsylvania, with 21 electoral votes, Gore won by a margin of 50.6 percent to 46.4 percent, but the GOP has picked up 4 percentage points in party ID. It’s also made gains in New Mexico and Oregon.

Meantime, Republican ID is also up in six “light red” states — narrowly carried by Bush — with a total of 70 electoral votes, topped by Florida, where the GOP has gained 6 points.

Other states in this category are Arizona, Arkansas, Missouri, Tennessee and West Virginia. In two other narrowly-for-Bush states, New Hampshire and Ohio, the GOP has lost ground slightly.

Pew and its director, Andrew Kohut, by no means regard the party ID numbers as the final word on the 2004 election, of course.

Pew’s lengthy report on the 2004 political landscape, titled “Evenly Divided and Increasingly Polarized,” says that “because Republicans traditionally turn out to vote in higher numbers than do Democrats, the current division in party affiliation … could provide the GOP with a slight electoral advantage.”

Kohut told me that “a few months ago, the Republicans were poised to do very well on the strength of Bush’s response to terrorism. Now, though, discontent over the Iraq war and the economy have brought down his approval ratings and re-elect numbers to equal levels.”

Indeed, Pew shows that Bush’s approval rating in October was at 50 percent and his disapproval at 42 percent — the narrowest margin during his presidency.

The liberal Democracy Corps, which tracks most national polls, showed that Bush’s average for October was 51.9 percent, down from 53 percent in September, 56 percent in August and 69 percent in April amid the Iraq war.

According to Pew and a number of other recent polls, a “generic” unnamed Democratic nominee ties or beats Bush in a head-to-head matchup.

Pew found that “a year before the election, the divided electorate looks strikingly similar to the one reflected in exit polls from the 2000 election.” The electorate is split 50-50 between Bush and the Democrat. Whites favor Bush by about the same margin, as do men, married persons and regular church attendees.

What may be dangerous to Bush is that he has lost ground among independents, who split 51-49 in his favor in 2000, but now divide 52-48 against him.

On the other hand, in every poll, Bush beats a named Democratic opponent. In the Pew matchup, he beat Rep. Richard Gephardt (Mo.) by 6 points; Sen. John Kerry (Mass.) by 8; retired Gen. Wesley Clark, 10; frontrunner Howard Dean, 11; and Sen. Joe Lieberman (Conn.), 12.

Averaging the performance of the Democrats, Pew found that Bush gained the most ground against them (as compared with an unnamed Democrat) among independents, conservative Democrats, women and those who believe that the war in Iraq was the right decision.

If Bush’s approval ratings are at their lowest point ever right now, it’s worth noting that in late 1971, President Nixon had just a 49 percent approval rating and in late 1983, Ronald Reagan’s was at 49 percent. Both won in landslides.

And President Bush’s father in 1991 still had a 56 percent approval rating and went on to lose the 1992 election.

Current approval ratings have yet to factor in an improving economy — the 7.2 percent third quarter growth rate, surging productivity and reduced numbers of new jobless claims — all of which are bound to help Bush.

Extravagant Democratic attacks on Bush’s credibility and trustworthiness have caused no dents in his reputation. An October Zogby International poll showed that 56 percent of voters are “proud” to have Bush as president and only 26 percent “ashamed.” By 64 percent to 31 percent, they consider him “honest and trustworthy.”

It would seem that Bush’s re-election rides on one thing: success or failure in Iraq. At this point, according to Pew, 60 percent of voters say that going to war was the right decision and only 33 percent say it was not. Democrats, who think it was wrong by a margin of 54 percent to 39 percent, are out of step — for now.