-- Former Utah Gov. Jon Huntsman, who banked on a strong showing in New Hampshire to propel his campaign only to finish a distant third to former Massachusetts Gov. Mitt Romney, suspended his campaign Monday, throwing his support to front-runner Romney. Rep. Michele Bachmann of Minnesota left the race after an abysmal finish in Iowa. Georgia businessman Herman Cain suspended his campaign amid persistent reports of sexual harassment.
-- Just before a debate Thursday, Texas Gov. Rick Perry, whose star faded after he burst into the race last year, announced he, too, was suspending his campaign after single-digit finishes in Iowa and New Hampshire.
-- Despite a ho-hum campaign in Iowa, initial returns showed Romney won the state's caucuses, squeaking by Rick Santorum by eight votes. However, by late Friday, the Republican Party of Iowa declared Santorum the winner by 34 votes, The Des Moines Register reported.
In New Hampshire, where Romney has a summer home, the former Massachusetts governor won easily.
Polls showed Romney with a strong lead nationally in the race to be the one to face incumbent Barack Obama in November. Several polls said the majority of Republicans, despite their lackluster backing, predict he'll be the party's standard-bearer, with a recent Washington Post-ABC News poll finding nearly six in 10 Republicans consider Romney as the party's best shot at defeating Obama.
Before the shake-up, none of the other Republican candidates seemed to be able to muster a sustained drive to knock Romney out of his front-runner post although they've tried. While some candidates have nudged Romney out of his top seed for a time, others have surged within spitting distance in second place.
Even though Romney in most major polls can't break that 40 percentage-point marker, it doesn't necessarily follow the GOP won't endorse him as their candidate when push comes to shove.
"Romney is the strong second choice of those whose first choice is another candidate," said political commentator Steven Schier, a political science professor at Carleton College in Minnesota. "That means that within the GOP, there will probably be no strong resistance to Romney as the party's nominee."
In a Washington Post-ABC News poll released before Perry withdrew and the revised Iowa results were released, Romney had the support of 35 percent of all Republicans and GOP-leaning independents nationwide, with former House speaker Newt Gingrich of Georgia and U.S. Rep. Ron Paul of Texas duking it out for second with about half the support Romney enjoys. Santorum had 13 percent, his highest level of the campaign.
Later in the week, however, several national polls showed Romney still in the lead but losing ground to Gingrich.
Before Perry announced his departure, at least one of his supporters called on him to drop out in the name of conservative unity, CNN reported.
Romney has moved up in the ABC News-Washington Post poll since mid-December, boosted by a huge bump in his perceived electability and a huge drop-off in national support for Gingrich.
In the days and weeks running up to the South Carolina primary, many pundits saw the Palmetto State as the last, best chance for Romney's opponents to block him.
"The last major hurdle for Mitt Romney's path to the nomination in 2012 is the South Carolina primary," Schier said before Saturday's polling, which saw Gingrich solidly trouncing Romney.
Despite the South Carolina results, Former New Hampshire GOP Chairman Fergus Cullen was blunter in an interview with the Boston Herald reported.
"The odds of Mitt Romney being the nominee are approaching 99 percent," said Cullen, who supported Huntsman. "To me, there were only two people standing on that stage -- Romney and Huntsman -- that were capable of winning a general election and doing the job as president."
But Floridians are telling Republicans not to get ahead of themselves just yet. After all Florida's primary is Jan. 31.
"You cannot wrap up this nomination without Florida," said Sid Dinerstein, the chairman of the Palm Beach County GOP. "And if you don't win Florida you're almost back to square one."
The Sunshine State's winner-take-all format -- it awards 50 delegates, half of its usual total because the Florida GOP wanted to advance the primary -- means a non-Romney winner shoots ahead in the delegate race.
Public Policy Polling said its first poll in Florida shows Romney had a 41 percent-to-26 percent lead over Gingrich, with Santorum at 11 percent and Paul at 10 percent.
Results of the poll conducted before the South Carolina primary indicated two things were in Romney's favor in Florida and elsewhere -- voters are focused on the economy and on beating Obama.
Even the primary-caucus calendar favors Romney, a GOP strategist said.
After South Carolina's contest is Florida then Nevada, a state he won by a large margin in 2008, followed by a string of states -- Maine, Colorado, Minnesota, Arizona, Michigan and Washington -- he's favored to win leading up to March 6, also known as Super Tuesday, when 10 states hold caucuses or primaries.
"Two of the first three states -- Iowa and South Carolina -- were not favorable to Romney. But the next four states basically let Romney say, 'Let's shut this thing down,'" Kyle Kondik, a political analyst with the Center for Politics at the University of Virginia, told The Hill. "You wonder where these candidates can even compete. … They can't just cede three or four primaries to Romney, but where do you go if you're Newt [Gingrich] or [Rick] Santorum?"
This year delegates are being awarded proportionally until April, so candidates, if they have the resources and the stamina, can stay in the race for a while. But if Romney can check state after state in the win column, it would be hard for any of his opponents to rally against him, raise the cash and build the infrastructure to really challenge Romney on Super Tuesday, political observers said.
"The GOP has dated other candidates over the last several months," Schier said, "but they seem content, after sewing some wild oats … to settle down and marry Romney."
Biologists detail four new deep-sea 'killer sponges'
Pistorius testifies he didn't consciously pull trigger when he shot girlfriend