West Virginia Gov. Joe Manchin (D) will appoint a replacement to fill the seat of the late Sen. Robert Byrd (D) until November 2012, when both a special election and a general election will take place on Election Day.

Manchin is also considered the leading candidate to run in two years, even though Monday was filled with tributes to the longest-serving Member in history and not talk of the politics of the race to succeed Byrd.

The announcement about the special election timing came Monday afternoon from West Virginia Secretary of State Natalie Tennant after an ambiguous section of state election law cast some questions about how and when Byrd’s seat would be filled. Tennant dubbed the state election code an “interesting document” during her Monday news conference.

The news was not greeted with enthusiasm by Republicans, who had been hoping for a special election this November, when a Republican-friendly political environment might have negated Democrats’ overwhelming voter registration advantage in the state.

State and national Republicans could still try to force a 2010 election through a legal challenge, but that possibility seemed remote Monday.

“We haven’t closed [the door on] that possibility yet, but it seems unlikely we’ll be challenging this in court,” state GOP Executive Director Troy Berman said.

Berman said he believes public outrage could still spur the state Legislature to amend the election code to require the election be held this year.

“Thirty-one months is an incredibly long time for an unelected appointee to serve,” he said.

The National Republican Senatorial Committee declined to comment on that possibility Monday, but one Capitol Hill GOP operative said a Democratic state Supreme Court and the precedent set in a 1994 West Virginia Supreme Court of Appeals case would make any legal challenge an uphill battle.

Barring a legal challenge, West Virginia voters will pick both a special election and general election candidate on the 2012 ballot.

As far as who might actually succeed Byrd, Manchin’s interest in the Senate seat is no secret, and his term ends in 2012.

If, and more likely when, he runs, even Republicans acknowledge that he will be hard to beat. Manchin’s approval ratings are consistently in the 70s, and voter registration in the state as of November 2009 was about 661,000 registered Democrats to about 348,000 registered Republicans.

Manchin said Monday that he will not appoint himself to the position, which means he’s all but certain to appoint a placeholder and spend the next two years gearing up for a 2012 run.

Manchin will likely avoid appointing anyone with political ambition who might want to stick around after getting a two-and-a-half-year taste of Senate life.

That means Byrd aide and 2008 Congressional candidate Anne Barth (D) is likely not on the short list and state party insiders are counting out most every Democrat serving in the state Legislature.

Former state Democratic Party Chairman Nick Casey is perhaps the name that comes up most often in discussions on possible placeholders. Casey is a proven political operator but is known for his work behind the scenes rather than as someone who seeks the spotlight. But Casey is up for a federal judgeship, and some party insiders wonder if he’d be interested in forgoing that job for a two-and-half-year stint on Capitol Hill.

Another name that has been mentioned as a potential placeholder is state Democratic Party Chairman Larry Puccio, a former top Manchin aide who was just elected to his state party post over the weekend.

Another intriguing possibility is Manchin’s wife, Gayle Manchin.

Gayle Manchin sits on the West Virginia Board of Education. Her husband appointed her to the nine-year term in 2007.

One West Virginia Democratic insider said Monday that Gayle Manchin is well thought of, extremely popular with women and would be viewed as a serious Senator in her own right.

But that move might seem overtly political and could backfire against Manchin.

Another name being thrown around in Democratic circles on Monday was attorney Herschel “Ned” Rose, who isn’t exactly part of Manchin’s inner circle but served as Byrd’s campaign manager in 2006. Byrd and Sen. Jay Rockefeller (D-W.Va.) recommended Rose for a judgeship in 2008, but Rose eventually withdrew his name last year.

Then there’s the possibility of Manchin turning to a well-known and well-respected former party official who may be looking for a way to cap off a long and distinguished political career. That group might include former Gov. Gaston Caperton (D) or former Gov. Bob Wise (D), Manchin’s predecessor.

Rep. Shelley Moore Capito, the lone Republican in the state’s Congressional delegation, is the most often mentioned GOP name for a possible Senate run, and she is one candidate who might give Manchin a race. Both Manchin and Capito are scions from well-known political families in the state.

Mark Blankenship, a West Virginia pollster who is working for a Republican House candidate, pointed out that in 2012, Manchin would be on the same ballot with President Barack Obama, who lost the state by 13 points in 2008.

“I think voters have been wary of President Obama since his introduction in the state, and that will be a challenge Joe Manchin faces,” Blankenship said.

But one West Virginia GOP insider said running against the Manchin machine might simply be too big of a risk for Capito, who is known to be fairly risk-averse politically.

“I think she’ll stay in the House before she’ll run against Manchin. … I think she’d probably run against anyone other than Manchin,” the GOP source said.

Other options for Capito might be a gubernatorial run in 2012 or to simply stay in her House seat until the 73-year-old Rockefeller retires.

Both Republicans and Democrats said Monday that while filling the seat will be a difficult process, replacing Byrd will be impossible.

“There will never be another individual like Robert C. Byrd, so we recognize that up front,” Rep. Nick Rahall (D-W.Va.) said. “We bind together as a people, Republicans, Democrats and Independents, whatever your stripe, to try to further the legacy of the man. … He was a man of the people who never forgot from whence he came.”