So has Hillary Clinton's battle between Barack Obama been going on forever, or does it just seem that way?
When the battle effectively began--in Oct. 2006 when Mr. Obama declared he had changed his mind and was considering a White House bid--the average price of gas then stood at $2.20-a-gallon. Defense Secretary Donald Rumsfeld directed Iraq war strategy. House Speaker Dennis Hastert and Senate Majority leader Bill Frist called the signals in the Republican-controlled Congress.
And Eliot Spitzer, poised to win the governorship of New York, was a rising star in national Democratic politics. Katie Couric was just seven weeks into her new job as anchor of the CBS Evening News. Neither Peyton nor Eli Manning had won a Super Bowl.
But it's not just pages in a calendar. Political circumstances have also changed dramatically.
In the fall of 2006, the Iraq War dominated Americans' political agenda. The Democratic Party's anti-war base turned out strongly enough in November to dislodge Republican Congressional majorities.
That dynamic provided a crucial edge to Mr. Obama, whose initial opposition to the Iraq war set him apart from Mrs. Clinton. His edge on the war has since faded; the success of the administration's post-Rumsfeld troop surge in reducing violence, if not securing major political gains, has robbed the Iraq issue of some of its urgency.
The reverse has happened with the economy. In October 2006 the U.S. economy added jobs for the 38th consecutive months. The Dow Jones Industrial Average closed above 12,000 for the first time. A summer spike in gas prices had receded.
Now gas prices have hit new records, the Dow has fallen back below 13,000 after topping 14,000 in 2007, and the economy has shed jobs for three consecutive months. Just as the cooling of the Iraq issue has hurt Mr. Obama, the widespread expectation of recession has helped Mrs. Clinton, whose advantage among working class voters is built largely on memories of her husband's successful economic stewardship in the 1990s.
The candidates have changed their styles along the way. Moving from front-runner to underdog, Mrs. Clinton has replaced her campaign manager and chief strategist. Adapting tactics to openings Mr. Obama provided, she has shelved the quavering emotion of mid-winter New Hampshire for springtime displays of her attachment to firearms and taste for whiskey shots in Pennsylvania.
Mr. Obama's campaign has made adjustments of its own. The soaring speeches and mammoth crowds that fueled his rise in campaign donations and poll standings have lately proven powerless to stop Mrs. Clinton from carrying Ohio, Texas and Pennsylvania.
Seeking inroads with the sort of working class whites Mr. Obama needs, his strategists have increasingly moved him out from behind the podium in search of more direct contact with small groups of voters. They've also moved him from the bowling alley to the basketball court as he shoots for twin victories in Indiana and North Carolina on May 6 to halt Mrs. Clinton's new momentum.
Even the electorate the campaigns are talking to has changed in significant ways. According to government statistics, 3.7-million Americans have died since Mr. Obama and Mrs. Clinton began squaring off. Another 6.2-million Americans have gotten married, including Mr. Obama's press secretary Bill Burton.
The young daughter of Clinton communications director Howard Wolfson, just a year old when the contest began, isn't yet eligible to vote. However, the campaign-weary Mr. Wolfson notes, "she knows the names of all the candidates."
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