Gallup’s weekly presidential approval survey shows Barack Obama sliding to the lowest level of his presidency, 46%, while his disapproval ties its highest mark, also 46%, for the third time this year.   The approval rating has reached 45% once on the daily tracking polls, but this has been the lowest full-week rating of Obama’s term.  The survey doesn’t include any data on issues, but clearly the response to the Gulf oil spill is dragging down job-approval numbers in a manner similar to what happened to George W. Bush and Katrina.

Let’s take a look at some charts showing the declines created from Gallup’s download files for its weekly survey results.  First, overall job approval and disapproval numbers for 2010 (please note that I have adjusted the Y-axis in these charts to get separation for data lines):

Note that the times when approval and disapproval meet in 2010 are not necessarily associated with legislative policy (primarily ObamaCare), but with other events.  In early January, Obama had difficulty explaining how the EunuchBomber made it through the counterterrorism efforts that the White House assured us would keep us safe.  In April, Obama loses his bounce from the passage of ObamaCare, but it takes the Gulf spill five weeks to eat into Obama’s approval ratings — which it rapidly does, starting about two weeks after the blowout.  The Times Square bombing attack also coincides with this rapid deterioration.

On the internals, Obama has even more problems.  Look at the age demographics in 2010, for example:

The youngest voters still stick with Obama.  However, all other age demographics have dropped below 50% and are trending downward.  That’s especially true of 50-64YO voters and, to a slightly lesser extent, 30-49YO voters.  All are solidly below 50% in job approval, with voters over 50 years of age barely above 40%.

Income demographics also show an interesting deterioration:

The lowest income level still give Obama a favorable job approval rating — but not by much.  It peaked at 63% when ObamaCare passed, but has dropped eleven points since to 52%.  The most stable approval rating Obama enjoyed over the year in income demographics comes from those earning between $20K-$50K, which still only gives him a 49% approval rating.  The other two demographics show considerable volatility and have dropped sharply over the last four weeks to points that are  almost year-long lows.

Interestingly, the party identification demographics showed little change at all.  Democratic job approval ratings for Obama have been in the 80s all year.  Among Republicans, it has run the gamut from 14% to, er, 19%, and is currently at 16%.  Independents currently rate Obama at 41%, his lowest rating among them all year, but only down seven points from his previous high among independents in 2010.

In short, this data looks like Obama’s support has gotten increasingly marginalized to the poor and young, and even that seems to be slipping away from him — just more slowly than everyone else.

Update: Here are the results from the race/ethnicity demographics:

Approval ratings remained relatively stable for white and black voters, but Obama has lost considerable ground among Hispanics (-20 points) and non-whites (-11 points).  The constant attacks on Arizona’s immigration law appears to have either backfired among Hispanic voters or not been a factor at all.