The deeper one digs into the returns from this past election, the more portentous the results seem.
I know the dangers of deciding too soon that any one election is a turning point. I recall vividly how devastated Republicans were after Lyndon Johnson's landslide victory over Barry Goldwater in 1964. But four years later, Richard Nixon was on his way to the White House.
The Democrats were equally disconsolate after losing to George H.W. Bush in 1988, their third straight presidential defeat. But what Michael Dukakis could not do that year, Bill Clinton accomplished in 1992.
So quick turnarounds are not only possible but commonplace when so many voters hold their party allegiances lightly and so many more profess no party labels at all.
That bespeaks caution about the long-term significance of the back-to-back Democratic victories of 2006 and 2008, which restored the White House to Democratic hands and added about 10 Senate and 50 House seats to their ranks.
Barack Obama and his fellow partisans face all kinds of serious tests, inheriting from George Bush and the Republicans two wars; a financial meltdown; and dysfunctional health-care, energy, transportation and infrastructure systems -- and a budget deficit that may top a trillion dollars.
Nonetheless, there are signs in this year's returns of voter shifts that could herald a new political era -- and that certainly define the challenge facing the Republican Party.
Several of the most important are pointed up in memos I received this past week from Stan Greenberg, a Democratic pollster, and Steve Lombardo, a Republican consultant. They were done independently, but there were significant overlaps.
Greenberg's post-election survey for Democracy Corps found that the three most important reasons voters gave for supporting Obama concerned his promises to withdraw troops from Iraq, to cut middle-class taxes and to expand health insurance coverage.
In arguing that the returns spell the emergence of a "center-left" majority, replacing the "center-right" majority of Bush and the Republicans, Greenberg and his colleagues note that Obama won the debate on tax policy with John McCain by 51 percent to 42 percent.
If Democrats follow through by cutting taxes for most middle-class families, as Obama promised, then Republicans could lose one of their hard-rock advantages.
Lombardo, looking at the election from a Republican perspective, opens his memo with words of semi-comfort for his fellow partisans: "The Obama win was neither as big as some Democrats and members of the media have made it out to be nor as small as some of the GOP faithful would like to think." Obama got 52.7 percent of the popular vote, the best showing for a Democrat since LBJ in 1964 and the first majority since Jimmy Carter in 1976. But it doesn't compare to the Reagan landslide of 1984.
The details of the returns are more ominous for Republicans. Exit polls and actual returns, Lombardo notes, show Obama scoring in the suburbs and the metropolitan areas, especially among young and first-time voters, and among minorities.
He won most of the votes from the college-educated, and he won a slight plurality among men -- reversing the pattern of Bush's two victories.
In the end, Obama flipped nine states that had gone for Bush -- Nevada, Colorado and New Mexico in the West; Ohio, Indiana and Iowa in the Midwest; and Virginia, North Carolina and Florida in the Southeast.
That left Republicans with a shrunken base in the South and the border states, where rural and Appalachian counties delivered for the GOP, and on the Plains, where population is falling compared with the rest of the nation.
That is not a formula for future success. As Lombardo concluded, "Given the demographic trends in the country, the GOP is unlikely to win any future presidential elections if it is losing 95 percent of the black vote and 67 percent of the Hispanic vote."