On the eve of Barack Obama’s 100th day in office, the latest Gallup Poll finds that 65 percent of Americans approve of his presidency. Nearly two-thirds public approval is enough for any White House to celebrate. But as Obama nears the first milestone of his presidency, his approval rating remains in the middle of the ten presidents who preceded him, based on an extensive analysis of historic Gallup polling.

Obama's standing is as remarkable as it is distant from the grand expectations that greeted him on Inauguration Day. Obama has earned historically lofty support from his base. But the historically paltry support from his political opposition keeps Obama well short of the more popular presidents of less partisan eras.

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The president who campaigned on "turning the page" will hit his 100th day in the same black and white standing as George W. Bush. Obama will in fact likely cross the milestone as the most polarizing president of the modern era.

Wednesday will mark day 100. It's a Washington ritual to both fixate on the milestone and belittle it. And although an artificial ritual at that, 100 days has become the traditional first landmark for reflecting on a new president.

Obama will come to that milestone a significantly more popular president than his three most recent predecessors, a notable accomplishment. He will also be short, on mean and median, of the public standing of half the presidents' since Dwight Eisenhower. Ike was the first president that Gallup repeatedly polled over the first 100 days.

Americans' view of Obama has stabilized in recent weeks. It allows for a firm sense of where the president stands on the cusp of day 100.

It was Franklin Roosevelt who began the 100-day count. FDR signed a breathtaking 15 major bills into law before the milestone passed. By comparison, Obama has signed 6 pieces of legislation. And so like most presidents since Roosevelt, Obama wrestles with the long shadow of FDR's precocious scorecard.

In the Obama administration's words, the first 100 days is a "Hallmark holiday." But it's a holiday Obama will recognize himself, with a prime-time news conference. The White House goal, like all administrations, is to steer the public view of the "holiday" because not only political junkies are watching.

The currency of a president's power is his popular support, as Obama's team knows. As Americans gauge their president at the doorstep of day 100, below are four significant trends to watch.

Obama's popular, but no JFK

The bar is 65. That's the average 100-day approval rating for the ten presidents between 1953 and 2009. Obama will likely finish his first chapter short of that bar, at 63 percent on average. That places Obama between Richard Nixon and Jimmy Carter in the public's view.

Obama fairs slightly better more recently. He may hit day 100 at 65 percent, where he stood Monday. If his approval holds at 65 on day 100, Obama’s final standing will rank sixth of the eleven recent presidents.

John F. Kennedy matches Lyndon Johnson for the highest average 100-day approval rating. But Johnson, like Harry Truman, owed his vaulted status to the death of a president.

Americans' early view of Kennedy is the most impressive in the modern era. JFK won the White House by the narrowest of margins. He struggled with policy in his first 100 days--including the Bay of Pigs debacle. But by the close of the first chapter of his presidency, Kennedy was able to unite the country like no other figure in the modern day. Seventy-seven percent of Americans approved of Kennedy over the course of his 100 days. On day 100, JFK's approval stood at 83 percent.

Perhaps more striking, only an average of 6 percent of Americans disapproved of Kennedy over his first 100 days. Obama will likely average four times JFK's disapproval. He stands at 25 percent. That's twice the modern average and ranks the third worst of the most recent eleven presidents. Bush was worse however, by a point. Clinton was worst of all, with an average disapproval rating 6 points above Obama.

The reason Obama's in the company of Clinton and Bush? Polarization.

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The Polarizing 'Post-Partisan'

Obama is likely the most partisan 100-day president of the modern era, but only by a hair's margin. Obama's partisan gap averages 60 percentage points. Bush was the most partisan modern president until Obama, at 57 points. Clinton closed his first 100 days with a 51-point gap. The partisan gap is the margin between the high approval of a president's political party and the low approval of the opposition party.

The polarized view of Obama would hardly be notable if not for the tenor of Obama's candidacy. Partisanship has steadily risen since Clinton. But transcending the two tribes of Washington was the nucleus of Obama's campaign.

Polarization is rooted in trends from gerrymandering to partisan migration. Northeastern moderate Republicans became Democrats. Conservative southern Democrats became Republicans. Polarization became so pervasive over the past decade that more Republicans approved of Bush in his first chapter than Eisenhower or Ronald Reagan. Carter had 53 percent of Republicans behind him over the course of his 100 days, almost twice Obama's GOP support.

Obama's polarization was not fated. Between Obama's first and fifth week in office, Republicans approval of Obama dropped from 41 to 28 percent--where it holds today. Conservative Republicans drove that decline. Their support fell over that period from 36 to 19 percent, where it also roughly stands today.

By late February, Obama was a polarizing figure in the mold of Bush, as RealClearPolitics first reported. Obama's partisan gap has shifted between 63 and 65 percent in the past eight consecutive weeks. His last weekly average partisan gap, heading into his 100th day, is 64 points.

Obama is likely to close his 100 days with the same level of support from Democrats that Bush enjoyed from Republicans, nine in ten. Meanwhile, Obama trends 4 points worse than Bush with the opposing party. It's a slight difference. And notably, GOP ranks have slimmed down since 2001. It's likely more moderate Republicans who fled. That would leave a more conservative GOP to assess the new president.

Eight years ago, even Bush attempted to convey a bipartisan tone. "We are beginning to get a spirit here in Washington where we are more agreeable," he said on the anniversary of his first 100 days.

It's the contradiction that spotlights Obama's polarization problem. At Obama's inaugural address, the new president said, "the stale political arguments, that have consumed us for so long, no longer apply."

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National Optimism

The most impressive mark as Obama hits his 100th day is the mood of the country. Obama has often been compared to FDR, for no reason more than the dire economic conditions both presidents inherited. Americans generally rally around their presidents in times of crisis. But its no certainty that rally will proceed without fail.

For now, American optimism is coming back. The portion of Americans who believe the nation is heading in the right direction, since Obama took office, has more than doubled from 14 to 32 percent.

That improvement correlates more to Obama than the economy. Obama's approval steadily improved at the same pace even as the stock market hit its floor in early March and recovered. By comparison, when the Dow Jones average rose in mid March, the portion of Americans who believed that "economic conditions" in the country were getting better rapidly turned upward. Today, 34 percent of Americans believe the economy is improving. On March 9, when the Dow hit 6,440, only 15 percent of Americans said the same.

Obama's challenge ahead will be to keep optimism on the upswing. Reagan also enjoyed a steady rise in optimism early in his presidency. But the public mood stagnated by 1982 at still low levels. Americans' outlook did not fully turn positive until the close of Reagan's first term.

Holding the Center

It was Yeats who once wrote that when "things fall apart; the centre cannot hold." In broad terms, a president's mandate ebbs and flows with the support of that center.

Obama has held the center thus far. Obama is likely to close the 100-day milestone with about six in ten independents behind him. That would place Obama where Nixon stood, ranking perhaps seventh of eleven presidents.

Seven is no ranking to sniff at. Obama will likely close 6 points higher than Bush with independents over the 100-day term, and surpass Clinton by about twice that margin. George H.W. Bush closed his first 100 days with the approval of only 51 percent of independents.

But the center is not assured. Two weeks ago Obama's independent support ebbed to 58 points. This last week it recovered to stand at 64-points strong. Absent significant GOP backing, the center is the keystone to Obama's mandate. And Obama can ill afford an average approval defining that mandate. He is a president with historic legislative ambitions who wins only standard public support. That's not the equation for major legislative prizes. For Obama to turn historic bills to law, in the months ahead, the center will have to do more than hold. Obama will have to wield a center overwhelmingly behind him.

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