Liberals are angry with President Obama - hey, what else is new? - and there is even sporadic talk about challenging him from the left in the 2012 Democratic primaries. It's hard to envision that actually happening, given that no human challenger appears to exist, but such talk seems symptomatic of Obama's political vulnerabilities on the eve of his last presidential campaign.

On the other hand, maybe the "Democrats in disarray" narrative is overhyped. It's frankly hard to know. For one thing, liberals are always angry with their leaders. That's how they roll. Fifty years ago, they constantly teed off on JFK; they said he was moving too slowly on civil rights and moving too swiftly into the big muddy of Vietnam. Fifteen years ago, they routinely savaged Bill Clinton for meeting the GOP more than halfway. Liberals frequently talked rebellion, but they stuck with Clinton when it counted most.

Granted, Obama has increasingly tested the patience of his own party base. He's the proverbial half-empty glass. He has championed health-care reform, albeit with concessions to the insurance lobby. He has launched troop withdrawals from Afghanistan, but he has more soldiers on the ground than when he took office. He has denounced the Bush tax cuts for the rich, but last winter he extended them. He once said it was wrong to wage war without congressional OK, but he has done so in Libya. He has vowed to defend Medicare and Social Security, yet, during the debt-ceiling crisis, he has put both programs on the table in his futile attempts to woo the Republicans who are bent on destroying him.

And at a time when the Democratic base wants him to trumpet job creation, he has ceded ground to the Republicans, echoing their emphasis on deficit reduction and spending cuts. During his address to the nation Monday night, Obama barely said a word about job creation. Instead, he declared: "Let's cut domestic spending to the lowest level it's been since Dwight Eisenhower was president." In response, liberals point out that the spending levels of the Ike era, circa 1955, are hardy sufficient to help put millions of people back to work in 2012.

Hence the angst of the activists. Rabbi Michael Lerner, who edits Tikkun (an influential magazine among liberal thinkers), said Thursday: "If liberals and progressives want their ideas considered in public discourse, we must challenge Obama in the primaries. . . . By accepting the distorted premise that the deficit is a greater threat to the economy than having one out of six Americans unemployed, Obama created the political mess in which he now swims, pretending to be fighting for those middle-income people he has already betrayed."

No doubt conservatives would laugh at Lerner's contention that Obama's policies are "significantly to the political right of those of the Nixon and Reagan administrations," but what matters is that many base Democrats believe this. Or, at the very least, they believe he has ill-served the economically vulnerable Americans who elected him. A new ABC News-Washington Post poll tells the tale; the share of liberal Democrats who strongly support his job policies has dropped 22 points - from 53 percent to 31 percent - since last year. The current share of black Americans who say his policies have helped the economy is 25 percentage points lower than in October.

Hispanics are also crucial to Obama's reelection prospects, but Gallup says those economically strapped voters are restive as well. Obama enjoyed 73 percent approval from Hispanics in December 2009; his current Gallup share is 52 percent. That's a potentially bad omen, because he needs strong turnout from Hispanics if he has any hopes of replicating his '08 swing-state victories in North Carolina, Nevada, Florida, and Virginia. He can ill afford a deep drop in enthusiasm.

But for every dire statistic, there is a caveat. Gallup also says that, despite all the teeth-gnashing on the left, Obama currently enjoys a 78 percent approval rating among all Democrats - one point higher than Clinton and Kennedy at the same point of their presidencies, and 41 points higher than Jimmy Carter, the last Democrat to be tossed from office. All of which suggests the talk about challenging Obama in the primaries is confined to the activist elite. (Another big talker these days is left-leaning Sen. Bernie Saunders. He's not even a Democrat.)

Besides, an intramural challenge would be an act of self-destruction. The last three presidents to lose reelection bids - Gerald Ford, Carter, and the senior George Bush - were first weakened in their own primaries. Carter was beaten in the 1980 election in part because liberal challenger Edward Kennedy had split the party. A president who can't unite his own base is ill-positioned to win over swing voters.

But Obama won't have that problem. The liberal grousers don't bother him; his main goal is to seize the middle ground. Indeed, if the Republicans keep veering too far right - as evidenced by their current no-compromise shenanigans, with America's full faith and credit twisting in the wind - they'll make his task easier. His televised address Monday was aimed squarely at the swing-voting independents who believe in bipartisan compromise. He wants to position himself as the voice of sweet reason, drawing a contrast with the crash-and-burn crowd.

The White House strategy won't quicken liberal pulses - if Obama continues to cede policy ground as proof of his reasonable nature, liberals will continue to scream "betrayal" - but the White House is clearly betting that they'll come around when the chips are down, particularly when faced with the prospect of a Republican victory. What are they going to do, vote for a conservative who's in hock to the tea party?

Obama's message will essentially be: The Other Side Will Be Worse Than Me. The restive Democratic base might buy it, given the options, but one truth is self-evident: The inspirational election of 2008 was so three years ago.

The American Debate:

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