Barack Obama hasn’t hit George W. Bush lows yet, but then again, neither did Bush until well into his second term — after Katrina.  In the latest Rasmussen tracking poll of likely voters, Obama has begun to sink again, this time falling to a new low in approval at 42%:

The Rasmussen Reports daily Presidential Tracking Poll for Tuesday shows that 24% of the nation’s voters Strongly Approve of the way that Barack Obama is performing his role as president. Forty-four percent (44%) Strongly Disapprove, giving Obama a Presidential Approval Index rating of -20 …

Overall, 42% of voters say they at least somewhat approve of the president’s performance. That is the lowest level of approval yet measured for this president. Fifty-six percent (56%) now disapprove of his performance.

Forty-four percent (44%) say the president is doing a good or excellent job on national security issues while 39% give him such positive marks on the economy.

At least at the moment, the downward pressure on his numbers doesn’t appear to be coming from his handling of the Gulf spill.  Rasmussen shows an almost even split on approval for that issue, 34/33, although that could change abruptly if the media catches up to the story.  Politico sees the tide beginning to turn against Obama on the issue.  In fact, it’s become so bad that Obama plans on breaking a 309-day streak:

Until this week, the Obama administration had largely managed to deflect responsibility for the Deepwater Horizon disaster onto others — vowing to keep a “boot on the throat” of BP, while slamming lax oversight on the part of federal regulators during the Bush administration.

But now, with crude lapping into the bayou, even Obama’s defenders have turned critical. A White House that prides itself on operational competence and message discipline has been frustrated by an environmental catastrophe it can’t predict, can’t control and can’t out-message — and the strain is showing.

A majority of Americans, by 51 percent to 46 percent, now disapprove of Obama’s handling of the crisis, according to a new CNN/Opinion Research Corp. poll. An Associated Press-GfK survey taken less than two weeks ago showed that only one-third of those polled gave Obama low marks for his response.

White House press secretary Robert Gibbs surprised reporters at the daily briefing Monday by announcing the president would answer questions about the spill in person Thursday — the first presidential news conference Obama has given in months.

That sounds as though the Obama White House has become a little desperate to contain the damage.  They have avoided press conferences ever since Obama went off-message in the last one, 307 days ago, and declared that Cambridge, MA police “acted stupidly” without knowing the details of the arrest of Henry “Skip” Gates.  The resulting embarrassment taught Obama’s handlers to keep him on the Teleprompter or in interviews with friendly media, where Obama has remained almost without exception ever since.

The internals for perceptions of Obama are looking very shaky indeed.  Only 39% approve of his performance on the economy; only 44% approve of his overall leadership.  Just 37% approve of his energy policies.  A microscopic 26% trust Obama in an economic crisis, and only 35% believe his ethics to be good or excellent.

Keep an eye on the numbers after Obama’s presser on Thursday.  He may get a bump just for showing up; if he does, expect him to start hitting the campaign trail ASAP.  If he doesn’t, don’t expect to see Obama much at all.

Update: Yid with Lid has some helpful and interesting charts.