Each presidential campaign is billed as more critical than the last. This election -- coming amid a global financial crisis and wars in Iraq and Afghanistan -- truly finds the country at a crossroads.

Republican Sen. John McCain presents himself as a maverick, attempting to distance his agenda from the policies of the Bush administration. McCain is an American hero who has served his country with honor, often standing up for the causes he believed in despite intense political pressure.

Democratic Sen. Barack Obama also promises reform and change. Since his passionate "Red State-Blue State" speech at the 2004 Democratic National Convention, Obama has staked out an optimistic vision of a more united America and a bipartisan approach to addressing problems in Washington.

With hope that he can deliver on that promise, Obama receives our endorsement.

This was a difficult decision because both candidates are flawed. Ideally Obama would have more experience and a long list of bipartisan accomplishments. Criticism that he has spent much of his time in the Senate running for the presidency is legitimate, and we were disturbed to see him break his pledge to abide by federal campaign spending limits.

McCain, whose campaign has lacked focus, made his most serious error in judgment with the selection of Alaska Gov. Sarah Palin as his running mate. McCain is well aware that the No. 1 qualification of a vice president should be readiness for the top job. Palin does not have the depth of experience to assure Americans she would be ready to run the country.

Obama's steady and analytical approach has stood out during the campaign. To make his vice presidential selection, Obama analyzed his own weaknesses and turned to Sen. Joe Biden, who offered deep foreign policy experience and the ability to assume the presidency if necessary.

Throughout his career, Obama has revealed an intellectual curiosity and openness to new ideas. He surrounds himself with academic experts and private-sector leaders, preferring research-based answers over partisan dogma. He seems willing to consider divergent viewpoints.

His approach to economic policy is revealing. Obama's appointment of centrist Jason Furman as his top economic adviser drew criticism from labor leaders and the far-left wing of the Democratic Party, in part because of the promarket Furman's links to Robert Rubin, a former Wall Street insider who served in the Clinton administration. But Furman is only one of a long list of economic experts -- including billionaire Warren Buffett -- to whom Obama has turned for advice. That he seeks out a variety of views on complex issues is refreshing.

There are numerous key policy differences, and in many cases Obama offers progressive and pragmatic ideas. His proposals on the economy, health care, energy independence, education, the environment and infrastructure investment -- while far from perfect -- offer an intelligent framework for progress.

The state of the economy makes it unlikely that either candidate will be able to fulfill the long list of promises he's made on the campaign trail. The Tax Policy Center says Obama's tax-cut pledges alone would reduce federal revenues by $2.9 trillion over the next 10 years, while McCain's would cut revenues $4.2 trillion.

Obama is less than convincing when he says he would go through the federal budget line by line with a scalpel, and McCain's call for an across-the-board spending freeze is arbitrary and impractical. Neither candidate adequately addresses the looming Medicare and Social Security funding crises.

Nor do the serious challenges awaiting the next president stop at our borders. He must also, in the words of Colin Powell, "fix the reputation that we've left with the rest of the world." Obama's multilateral approach to foreign policy improves the chances that America can begin to restore its stature and gain deeper support from its allies. Powell's endorsement, which followed a number of conversations with Obama, is a significant vote of confidence from one of the early pillars of the Bush administration.

If elected, Obama will need to prove his independence from predictable party politics and take a bipartisan approach to complex problems. He'll need to continue to emphasize personal responsibility as a bedrock American value. He and the country will need to remember the homeland security lessons of 9/11 and bring the Iraq war to a responsible end. Obama has properly rebuked Iran's nuclear aspirations and Russia's aggression, and he's promised a strong commitment to national defense. He seems determined not to let national security be an afterthought for his administration.

It would be a mistake to offer this endorsement without recognizing the nature of this moment in American history. The country is about to elect either its first African-American as president or its first woman as vice president. Both are long overdue, but Palin's shortcomings would likely overshadow the historic nature of her election. An Obama presidency would reaffirm for the country and the world the possibilities offered by a free, inclusive and democratic society. It would herald an important generational shift in American leadership and provide hope for a more unified nation.

Even after a bruising campaign by two strong candidates, Obama's optimistic message of unity endures. On Nov. 4, Americans will set a new course. In Barack Obama, they have a candidate who can inspire faith in better days to come.