The Des Moines Register, the largest newspaper in Iowa, backed Mitt Romney late Saturday in his bid for the Republican presidential nomination.

The much-anticipated endorsement gives the former Massachusetts governor special bragging rights just more than two weeks before Iowa’s critical presidential caucuses on Jan. 3.

Citing the candidate’s “sobriety, wisdom and judgment,” the editorial board said Romney was the most qualified candidate competing in the caucuses.

While the paper didn’t endorse Romney in his last run for president in 2007, the editorial board said voters now face a different GOP field and Romney “has matured as a candidate.”

“Rebuilding the economy is the nation’s top priority, and Romney makes the best case among the Republicans that he could do that,” the editorial board wrote.

The board hailed Romney for his “solid credentials,” saying he was the most likely candidate to see through “knee-jerk, ideological” perspectives and “bridge the political divide in Washington.”

Taking issue with the two other top-tier candidates, the paper claimed Romney stood out against former House Speaker Newt Gingrich, whom the board called “an undisciplined partisan who would alienate, not unite, if he reverts to mean-spirited attacks on display as House speaker.”

It also criticized Texas Rep. Ron Paul, who received an endorsement last week from the Daily Iowan, as someone with a libertarian ideology that would “lead to economic chaos and isolationism.”

Also significant, the board somewhat defended Romney against a line of attack taken by opponents who criticize him as a “flip-flopper.”

“Though Romney has tended to adapt some positions to different times and places, he is hardly unique. It should be possible for a politician to say, ‘I was wrong, and I have changed my mind’,” the paper wrote.

But the paper still reserved questions over his changing tune on issues such as abortion and said it was up to the voters to decide “whether such subtly nuanced statements express Romney’s true beliefs or if he’s trying to have it both ways.”

The editorial is the second major endorsement for Romney in two days, coming on the heels of Friday’s nod from South Carolina Republican Gov. Nikki Haley. South Carolina’s primary, set for Jan. 21, is the first presidential contest in the South and the third overall in the early voting season.

In early December, Romney scored another endorsement from Iowa’s Sioux City Journal, which described the candidate as “best prepared through experience, skills and qualities to lead the country.”

Romney has taken heat all year for running what many political observers call a lackluster effort in Iowa. He has campaigned in the state far less than Gingrich, Bachmann, Rick Santorum and Rick Perry. He opened up his first office in Iowa just last month.

His campaign chose not to secure a spot in the non-binding but closely watched Ames Straw Poll in August, which measures a campaign’s organizational strength in the state.

Romney won the straw poll during his first presidential bid in 2007, but fell short of winning the caucuses five months later.

While Romney didn’t actively seek a straw-poll win this time around, he was still on the ballot in August and took sixth place. Bachmann narrowly won the contest, with Paul following closely behind.

Romney has since returned to the state multiple times. He’s held steady at or near the top of polls in the state for much of the year, until recently, when Gingrich surged ahead in the GOP horserace.

According to an American Research Group poll taken Dec. 8-11, Romney placed second in Iowa with 17 percent of support among likely caucus voters, while Gingrich took first with 22 percent. Paul tied with Romney at 17 percent.

Reacting to the paper’s endorsement, Santorum, who’s spent most of his resources campaigning in Iowa, indicated he was not expecting the nod.

“Shocked! I would have been concerned that I was doing something wrong if they’d endorsed me,” he said Saturday at a campaign stop in Harrison County.

Bachmann’s campaign put out an official statement from the congresswoman: “I respect the decision of the Des Moines Register editorial board, but I disagree with their rationale and analysis of my campaign.”

Her spokeswoman, Alice Stewart, elaborated while at a campaign stop in Iowa, saying it was “disappointing” to read the editorial’s comments about Bachmann. The board described her as “an impressive fireball who can absorb and regurgitate tons of information, even if some of it turns out to be inaccurate.”

Stewart argued that Bachmann “didn’t get anything wrong” in her meeting with the editorial board and pointed to “some major serious” mistakes made by other candidates.

“We certainly would have liked to have the endorsement, but it doesn’t stop what were doing,” she said.

While the paper’s endorsement is highly coveted, it does not necessarily spell success for a candidate.

In the last election cycle, the paper endorsed GOP Sen. John McCain of Arizona, who didn’t actively campaign in the state and took third place in the caucuses, while former Arkansas Gov. Mike Huckabee pulled off a surprise victory.

At the time, the editorial board said Romney exuded “executive discipline” but decided to back McCain instead, saying the senator was the “most ready to lead America in a complex and dangerous world” and more likely to inspire “confidence in his leadership.”

On the Democratic side, the paper backed then-Sen. Hillary Clinton of New York, who later placed third in the caucuses behind then-Illinois Sen. Barack Obama and former North Carolina Sen. John Edwards.

The newspaper has long endorsed candidates for the general presidential election, but it began making endorsements for the caucuses in 1988.

Since then, three of its choices went on to win the contest: Bob Dole in 1988 and 1996 and then-Texas Gov. George W. Bush in 2000.

In addition, three endorsees eventually secured the Republican nomination: Dole in 1996, Bush in 2000 and McCain in 2008.

Only one of its chosen candidates — Bush in 2000 — went on to win the White House.

— CNN’s Robert Yoon, Peter Hamby, Oliver Janney and Chris Welch contributed to this report.