The end of the midterm election marks the official start of a 2008 presidential campaign that promises to be the most unpredictable and wide open White House contest in modern politics.
The campaign is tempting a diverse mix of ambitious leaders with the unique chance to pursue the White House without a sitting president or vice president in the way of their dreams. That hasn't happened since President Calvin Coolidge and Vice President Charles Dawes sat out the 1928 campaign.
Sens. Hillary Rodham Clinton, D-N.Y., and John McCain, R-Ariz., widely considered the front-runners in their respective parties, dominate the early positioning. An intriguing wild card is freshman Sen. Barack Obama, D-Ill., the only black in the Senate, who says he is seriously considering a presidential run.
The second tier
Among the other alternatives are Massachusetts Gov. Mitt Romney, a Republican, and former Democratic vice presidential candidate John Edwards. Former New York City Mayor Rudy Guiliani could change the dynamics of the race if he decides to run.
All the potential candidates were reluctant to appear too personally ambitious with Senate control hanging in the balance in the midterm.
McCain's top advisers planned a Wednesday meeting to examine the 2008 landscape. Clinton, the only serious potential presidential candidate on the ballot Tuesday, made a victory tour of New York state Wednesday.
Clinton brushed aside questions about 2008.
"We have some unfinished business. I'm hoping that starting next week, we'll have a more receptive Congress," she said, adding, "All I'm doing is thinking about going back to work next week in Washington. I'm going to relish this victory."
In an NBC interview, McCain cautioned against reading Democrats' near sweep of closely-contested midterm races as a portent for 2008.
"I'm a student of history," McCain said. "We lost badly in 1976. Ronald Reagan charted our course in 1977. We came back in 1980 and gained the presidency and majority in the United States Senate.
"Look, these things are temporary. ... We'll get back on track."
'A donnybrook like we haven't seen'
Edwards was preparing a 16-city tour to promote his feel-good new book, "Home: The Blueprints of Our Lives." Not coincidentally, the book was scheduled for release exactly one week after Election Day, and the tour goes through Iowa, New Hampshire and South Carolina.
Hopefuls from both parties already have been campaigning in those early presidential primary voting states.
"This is going to be a donnybrook like we haven't seen in Iowa," said Democratic strategist Jeff Link, who is working for home state Gov. Tom Vilsack's underdog campaign. Link said the state's voters have been wrapped up in the midterm races, but he expects they will turn to presidential politics "pretty quickly, because the caucuses are 13 months away."
Democratic Sen. Evan Bayh of Indiana, who has been an impressive fundraiser, said Wednesday he would wait until Christmas before deciding on a presidential bid, and told The Associated Press in an interview: "I think the public is ready for a break from politics."
The midterms effectively ended the presidential ambitions of two Republican senators - Rick Santorum and George Allen, whose Senate fate was still uncertain.
The campaign also damaged the prospects of Sen. John Kerry, the 2004 Democratic presidential nominee who wasn't even on the ballot. Like other 2008 hopefuls, Kerry had been traveling the country to raise money and attention for midterm candidates, and he put his foot in his mouth by suggesting that students who don't study could end up stuck in Iraq.
Kerry said it was a botched joke about Bush, but Republicans used it to suggest that the Vietnam veteran was criticizing U.S. troops.
Kerry was forced to cancel campaign appearances so he wouldn't become a distraction to Democratic candidates, but his advisers promised he would be back out soon to talk about 2008.
Kerry and other Democratic hopefuls will have a tough challenge in Clinton should she decide to enter the race. She is the clear fundraising leader and has worked to build a moderate image in the last couple of years. Still, some Democrats are concerned that she is so polarizing that she couldn't win a general election.
The Obama factor
Bayh and Vilsack can claim Midwestern values and experience winning elections in red states, although both have to build their name recognition outside their home base.
Other Democrats are claiming the foreign policy credentials to lead in a time of war - Sen. Joe Biden of Delaware is the top Democrat on the Foreign Relations Committee, Arkansas' Wesley Clark is a retired four-star general and New Mexico Gov. Bill Richardson is a former ambassador to the United Nations who has represented U.S. interests throughout the world. But all three have a challenge to rise to the top tier of candidates, as do Sens. Chris Dodd of Connecticut and Russ Feingold of Wisconsin.
The biggest question on the Democratic side is whether Obama will enter the race. The senator has been drawing a rock star reception on travels around the country this year that is unmatched by any other potential candidate. Yet he's only served two years in the Senate, leading to questions about whether he has the credentials to be president.
Still, Obama and Clinton were tied at the top of an Associated Press-AOL News poll conducted late last month. Each were selected by about one-fifth of registered Democratic voters surveyed.
On the Republican side, Secretary of State Condoleezza Rice, Giuliani and McCain were essentially tied with support of about one in 10 questioned in the same poll. Rice has insisted that she will not run.
The Republican side splits into three tiers, with McCain and Romney at the top because of their early organization and broad appeal. McCain has alternately challenged and embraced Bush, building a reputation as a maverick who isn't afraid to speak his mind. Romney is clearly positioning himself as the alternative to McCain, especially among religious conservatives.
Others who have raised significant funds are Guiliani and Senate Majority Leader Bill Frist. But both face questions about whether they can win support from Republican primary voters - Guiliani because of his liberal views on social issues including gay rights, gun control and legal abortion and Frist because of problems in the Senate caucus that he led.
More long-shot candidates on the GOP side include New York Gov. George Pataki, Sens. Sam Brownback of Kansas and Chuck Hagel of Nebraska, Arkansas Gov. Mike Huckabee, Reps. Duncan Hunter of California and Tom Tancredo of Colorado, former House Speaker Newt Gingrich and former House Majority Leader Dick Armey. Most face problems building name recognition or raising the money that will be necessary to compete in this highly competitive race.
Republican New York City Mayor Michael Bloomberg could launch an independent presidential campaign, with billions in the bank to self-fund. He has denied that he is interested - most recently while promoting Connecticut Sen. Joe Lieberman's successful independent bid for re-election - but some of his friends have privately promoted the idea of his outsider appeal.
Each side has two imposing figures who have insisted that they are not running to replace Bush but could turn the race upside down if they changed their mind. They are Rice and former Vice President Al Gore.