A sigh of relief could be heard throughout Senate Republican offices on Capitol Hill Wednesday morning when, after weeks of mounting speculation about his plans for 2008, Sen. Thad Cochran (R-Miss.) released an e-mail stating his intention to run for a sixth term.

The news came without fanfare and without much of a heads-up to Congressional colleagues, despite the fact that for weeks several Hill insiders said privately the Senator was leaning toward retirement.

In an interview Wednesday afternoon, Cochran conceded, “I hadn’t really decided until this morning to definitely seek reelection.”

Cochran said he wanted to wait until after last week’s state elections because he didn’t want his fundraising or announcement to “detract from [Gov.] Haley Barbour’s (R) campaign.”

The Senator said he didn’t really consult anyone but made a “personal decision” about his re-election and said the decision came down to whether “I felt comfortable running for re-election and would enjoy another six years in the Senate.”

One Republican strategist acknowledged Wednesday that the party, which has seen five Senate retirements so far this cycle and already is expected to be strapped for cash in defending open seats, dodged a bullet with Cochran’s decision to run again.

“Having no idea what he was going to announce, some Republicans were holding their breath,” the strategist said. “Republicans did not need another seat to spend money in … and I don’t think [Cochran’s seat] was a lock for Republicans without him there.”

The source acknowledged that there had been some concern that former Mississippi Attorney General Mike Moore (D) would enter an open-seat race. Moore is well-known in the state for leading the legal fight waged by several states against the tobacco industry and helping to negotiate a payout worth millions of dollars. Moore is one Democrat who could have raised a lot of money very quickly, but even Democrats acknowledged Wednesday that Cochran is not likely to face much serious opposition now that he’s running again.

“We’re thrilled,” National Republican Senatorial Committee Chairman John Ensign (R-Nev.) said. “Beyond that, what can you say? It’s a great day.”

Cochran’s announcement also likely was welcome news for House Republicans. There was some speculation in recent weeks that both Republican Mississippi Reps. Chip Pickering and Roger Wicker would consider a run for the seat if Cochran retired. Although Pickering already has announced his plans to retire from the House at the end of the 110th Congress, Wicker’s entry into the race would have created another open — albeit safe — Republican seat. If both Wicker and Pickering had run, a statewide primary battle between two big GOP names in the Magnolia State also would have put a drain on party fundraising efforts elsewhere.

Cochran’s decision also means that Pickering does not have to go through the awkward dance of declaring for a Senate seat after he already had announced his intention to retire. Pickering, who is just 44, is widely expected to run for the Senate some day, and he now can focus on finding a lucrative job in the private sector — at least until Cochran or Senate Minority Whip Trent Lott (R-Miss.) decide to retire.

After Cochran’s announcement, both Pickering and Wicker were quick to praise the decision.

“It is great news for Mississippi that Senator Thad Cochran has decided to seek re- election in 2008,” Pickering said in a statement. “His effective experience and leadership will continue to benefit Mississippi and guide America as a voice of reason and competence in the U.S. Senate.”

“Thad Cochran exhibits the sort of statesmanship that our country needs at a time like this,” Wicker said. “So if people feel that Mississippi dodged a bullet it’s also true that this is also very good news for the country as a whole.”

If Cochran didn’t consult anyone in advance about his decision, he certainly received ample amounts of encouragement to run again from state and national Republican officials.

One GOP source in Mississippi’s state House said Barbour and Cochran “are personal friends and very, very strong political allies. Gov. Barbour gives Sen. Cochran much of the credit for funding Hurricane Katrina recovery programs, and the Senator’s tenure has been good for Mississippi across the board. They talked about whether the Senator would run again and … [Barbour] is elated with Sen. Cochran’s decision.”

Wicker said he encouraged Cochran “in the strongest, most prayerful terms to run again for re-election. I can not tell you how delighted I am.”

Emily Pierce and Erin P. Billings contributed to this report.