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Waiting in line for two-and-a-half hours is rarely an exciting experience. But when my son and I voted early—he for the first time—at a community center in Rockville, Md., both of us were inspired by the hundreds of other people intent on exercising democracy’s most basic right.

In our deep blue county, this was largely an Obama crowd, crossing the boundaries of race, class and age. It was white, African American and Latino, young, middle-aged and old. These citizens eager to lift their voices reminded us that in this campaign, one coalition includes almost every kind of American. If Obama wins, he will owe his re-election to a little bit of all of us: blue-collar white voters in the Midwest, upscale voters in the Northeast and on the West Coast, an overwhelming percentage of Latino voters turned off by a new nativism on the right, and near unanimous solidarity on his behalf among African Americans. Obama is not the sort to think about dismissing 47% of us.

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The sweep of the Obama coalition represented in that snaking line led my son and me to conclude something else: The President Obama of 2012 may no longer stir the jubilation called forth by the Barack Obama of 2008. But the hope and resolve he spoke of then have not vanished.

Yes, those feelings have been tempered by hard times and four years of bitter political struggle. Obama appears now less as a savior than as a human being with flaws and virtues, failures and successes. The hope of four years ago has transformed itself into something more mature and durable: a confidence in what an increasingly diverse, tolerant and open America can achieve. It is a view that flatly rejects the fears of those who see our country in decline and who always insist that the good old days should be our standard for the future. A nation that has produced Greatest Generations in the past can do so again. Indeed, I think we’re doing so right now.

In making electoral decisions, voters sensibly combine hard judgments about where candidates stand with instinctive calculations about how character might influence their choices in situations we cannot imagine today.

Ronald Reagan offered the most widely honored question about the practical matters: Are you better off than you were four years ago? And for most of the country, the answer is yes. Obama inherited an economy in shambles—the GDP was shrinking at an annual rate of nearly 9% when he took office—and turned it around. Unemployment is well down from its peak, 4.5 million private-sector jobs have been created since January 2010, the stock market has doubled since it hit bottom, and the housing market is stabilizing. Mitt Romney can promise 12 million more jobs in the coming four years because Obama’s policies have already put us on track to produce them, courtesy of a revival of manufacturing, a rise in exports and a new wave of research and innovation.

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Most relevant to this year’s choice is the fact that the economy is in far better shape than it would have been if we had followed the counsel of Obama’s foes. They would have allowed the auto industry to collapse. They would have ignored history’s lesson that government must step in to stimulate economic activity when private demand plummets. We know from the experience of Europe that austerity leads to stagnation. Obama made the better choice.

Romney has at times condemned Obama’s stimulus plan while standing in front of enterprises returned to prosperity by the stimulus. Paul Ryan denounced the stimulus and then sought its succor for companies in his district. Watch what they do, not what they say.

Obama has revived a practical, sober and realistic foreign policy in the tradition of George H.W. Bush. Democrats crow about the killing of Osama bin Laden and thrill to Vice President Joe Biden’s handy bumper-sticker line “Osama bin Laden is dead, and GM is alive.” But behind the quip is a reality: Obama has transformed the war on terrorism from an all-purpose slogan designed to rationalize all manner of foreign policy adventures to a focused effort to keep the country safe. By ending the war in Iraq, winding down our commitment in Afghanistan and abandoning grandiose adventurism, he has redirected U.S. foreign policy toward the classic and sensible goals of preserving our power and influence and shaping an international environment congenial to our prosperity and our values.

Republicans bridle at the idea that Obama has restored respect for our country around the world. But it’s true. An Obama defeat would threaten many of his diplomatic achievements, including building what one pro-Western ambassador called “a successful coalition of the unlike-minded and unwilling” to confront Iran.

The strongest endorsement of Obama’s choices came from his opponent. In the third debate, Romney abandoned months of bellicose rhetoric and lined up behind one Obama decision after another. In this polarized political era, poll-tested imitation is about the only form of flattery we can expect. When Romney declared that “we don’t want another Iraq,” he was blessing the transition from George W. Bush’s era to Obama’s.

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Obama’s decision to ignore cautious political advisers and see through the health care reform fight came at great political cost. Even some of his allies think the electoral price was too high. But this is a measure of Obama’s fortitude. By bringing the promise of health insurance to tens of millions of our citizens, Obama ended a national scandal. No other wealthy nation allows so many to live without basic coverage for illness or to rely on emergency rooms as a last resort. They either arrive there long after the opportunity to get well has passed, or they survive only to face years, sometimes a lifetime, of debt. The Affordable Care Act is an achievement worthy of our great reforming Presidents.

Once again Romney’s behavior proves the point. He speaks of repealing Obamacare only in general terms. When it comes to so many of the specifics—on prohibiting insurance discrimination against those with pre-existing conditions, for example, or on making it easier for parents to cover their adult children—Romney winds up backing what Obama did.

Beyond these large questions are concrete Obama achievements: his support for women’s rights, including the Lilly Ledbetter Fair Pay Act; the end of “Don’t ask, don’t tell” and his endorsement of gay marriage; passage of Wall Street reform, including the creation of the Consumer Financial Protection Bureau; reform of the student-loan program; his appointments of Elena Kagan and Sonia Sotomayor to the Supreme Court, checking the right-wing drift in the judiciary that gave us decisions like Citizens United; and many of the investments in the stimulus package, notably in clean energy. In quieter times, these would be playing a much larger role in the campaign.

All are part of the case for Obama. But the best reason for his re-election goes back to what motivated so many middle-of-the-road voters four years ago. Americans who want to replace polarization with balance, extremism with moderation, obstruction with problem solving and blind partisanship with compromise need Obama to win again. An Obama defeat would empower those whose go-for-broke approach to politics is largely responsible for the distemper of our public life and the dysfunction in Washington.

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This election does not represent a choice between left and right. It represents a choice between balance and a new, extreme form of conservatism. This new conservatism cannot accept any tax increases as part of a deal to reduce the deficit. For all his attempts to sound moderate in the campaign’s closing days, Romney has not altered the response he gave during a Republican-primary debate rejecting a hypothetical deal involving a 10-to-1 ratio between spending cuts and tax increases. This refusal to acknowledge the need for more revenue is a recipe for eviscerating government—and the cuts, as Ryan’s budget shows, would fall disproportionately on programs for Americans with the lowest incomes.

The new right has broken with conservatism’s past—and our country’s most constructive traditions—by adopting a new and radical individualism that largely ignores our country’s gift for community.

The America of Alexander Hamilton, Henry Clay, Abraham Lincoln and both the Republican and Democratic Roosevelts understood that government has a role to play in tempering the market and making investments the market depends on but will not make itself. The new conservatism measures freedom almost entirely in terms of the share of the nation’s GDP that flows to the state, as if spending on Medicare, Social Security, student loans, community colleges and infrastructure improvements somehow made us less “free.” And in the face of growing economic inequality, the new conservatism regularly discounts or condemns government’s role in leaning toward modestly greater equity, promoting upward mobility and checking concentrated economic power. It is this variety of conservatism that Romney bowed to in the primaries and would be forced to accommodate if he became President, whatever his constantly shifting views might actually be.

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Obama, to a fault, devoted enormous energy during his first 21⁄2 years in office trying to move his opponents to compromise. Thus was almost a third of his stimulus plan devoted to tax cuts. Thus did he model his health care plan after Romney’s in Massachusetts. Thus did he seek a deal with House Speaker John Boehner during the debt-ceiling confrontation that, if enacted, would have disappointed many of the President’s progressive supporters. Only those who confuse compromise with capitulation can claim that Obama did not try mightily to keep his promise to end partisanship in Washington.

Obama should win a referendum on his stewardship. But this is also a choice—a “big choice,” just as Romney says—between moderation and a return to an approach to government more suited to the Gilded Age than to the 21st century. Obama is battling to defend the long consensus that has guided American government successfully since the Progressive Era. It is based on the view that ours is a country whose Constitution begins with the word we, not me, and that the private success we honor depends on a government that serves a common good and remembers the most vulnerable among us. The task of our moment is to revive that long consensus and renew it. Of the two major candidates, only Barack Obama accepts this mission as his own.

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Dionne is a Washington Post columnist and the author of Our Divided Political Heart (Bloomsbury). He is a professor at Georgetown