Romney emerges from the crowd

Allen's radically reduced prospects will make it less likely that McCain can duplicate his 2000 triumph in New Hampshire's primary. As one seasoned New Hampshire Republican says, "It is difficult to capture lightning in a bottle twice." It will be particularly difficult for McCain to do so because there is apt to be a spirited New Hampshire contest on the Democratic side. This would draw independent voters who were crucial to McCain in 2000, when he thrashed George W. Bush, receiving 115,606 votes (48.53 percent) to Bush's 72,330 (30.36).

But Bush won the Republican part of the Republican primary, in this sense: New Hampshire independents can vote in either party's primary, and 34 percent of McCain voters identified themselves as independents. A 41 percent plurality of the Republicans voting favored Bush, 38 percent favored McCain.

If one discounts President Truman's brief interest in seeking a second full term in 1952 -- he renounced running on March 29 -- and the ineffectual attempt by his vice president, Alben Barkley, to secure the nomination, 2008 will be the first election in 56 years with neither an incumbent president or vice president seeking a nomination. If you do not discount the Truman and Barkley episodes, 2008 will be the first such election since 1928.

So the presidential field is uncommonly open, and there is a palpable desire in the country to shuffle the political deck. In their new book "The Way to Win: Taking the White House in 2008," Mark Halperin of ABC News and John F. Harris of The Washington Post suggest why:

"When the current President Bush completes his full second term, it will be the first time since James Madison and James Monroe almost two hundred years ago that back-to-back presidents both served all eight years of two elected terms. Put another way, two of the most divisive figures in this country's history will have commanded the White House for sixteen consecutive years."

Such circumstances should entice many aspirants into the race. Yet with Allen much diminished and perhaps out of contention, and with Rudy Giuliani not yet doing serious groundwork for a national campaign, the Republican field is already down to two. That is good for only one of them: Romney.