Facing stubborn jobless numbers and the most pessimistic public since his inauguration, President Obama’s key base groups give him some of their lowest marks to date, according to a new Washington Post-ABC News poll. Indeed, Obama’s job approval ratings among Democrats, liberals and those under age 30 tie or set record lows in the survey, and the numbers are no better on his handling of the economy, jobs, or the deficit.

Among his most natural base — those who voted for him in 2008 — 79 percent approve of his job performance, and 70 percent rate him positively on the economy. Still fewer liberals, 69 percent, approve of the job he’s doing as president, tying a record low from July. And for the first time since he entered office, fewer than half of adults under age 30 approve of Obama. Voters under age 30 supported Obama by roughly 2 to 1 in 2008

Why the weakening base support?

The president may be feeling the brunt of two recent national developments: deflated hopes that Obama can turn the economy around and a sense that he gave in too much to Republicans in the debt ceiling negotiations. On the first count, the percentage of Democrats who say Obama’s economic program is making the economy better dropped from 60 percent in January to 33 percent in the new poll (more say he’s having no impact).

On the second, fully half of Democrats in a July Post-ABC poll worried that Obama was “too willing” to compromise with congressional Republicans in the debt ceiling negotiation. The result? In the new poll, almost two in three Democrats, liberals and those under age 30 — all who supported Obama in droves in 2008 — say the country is seriously off on the wrong track.

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