"You've seen the gray hair on my head to show you what it means to fight for change," Obama said in Madison, Wisconsin. "And you've been there with me.  And after all we've been through together, we can't give up now."

Romney, the former Massachusetts governor, having long- since abandoned his one-time support for abortion rights and a government health-care mandate, began the year branding himself "severely conservative" as he slogged through a crowded Republican primary in which party activists put a premium on ideological purity. He ends it calling himself a bipartisan consensus-builder who will bring about "real change" -- the kind Obama promised yet didn't deliver.

Yard Signs

"I'd like you to reach across the street to that neighbor with the other yard sign -- and we'll reach across the aisle here in Washington to people of good faith in the other party," Romney said in Fairfax, Virginia.

The president and his challenger were both responding to developments beyond their control, said historians who watched the race.

"When Obama came to office, people were framing him as the new Franklin Roosevelt -- he was going to come in and fix this economic mess and offer a new beginning," said political historian Beverly Gage of Yale University. "It's pretty remarkable how different this election is now, and how really vulnerable he has seemed all along, compared to something like the 1936 election. Obama has ended up owning the economic crisis in a way that someone like Roosevelt didn't seem to, and that has been his biggest stumbling block."

Jobless Rate

The unemployment rate, at 7.8 percent as Obama took the oath of office on Jan. 20, 2009, spent 43 consecutive months above 8 percent before settling back to 7.9 percent in the latest jobs report on Nov. 2.

Republican Ronald Reagan is the only president to have been re-elected since World War II with a jobless rate above 6 percent. The rate was 7.2 percent on Election Day 1984, having dropped almost 3 percentage points in the previous 18 months. Through October this year, the rate has declined 1.1 points in the same period under Obama.

It was impossible for Obama to rekindle the sense of history that pervaded his first campaign, said presidential historian Robert Dallek.

"There's only one first time for being the first African- American to win," Dallek said in an interview. "It's faded, it's four years later. You can't just generate the kind of excitement and enthusiasm that Obama could the first time -- circumstances change."

Primary Battle

Romney, too, had the challenge of running at a time ill- suited to his political profile as the former governor of a Democrat-dominated state who had previously been known more as a pragmatist than a party soldier.