Byrd's body will lie in repose in the U.S. Senate chamber Thursday and will then be flown to Charleston. Following a procession through the city, the body will lie in repose in the well of the Capitol rotunda overnight Thursday. A memorial service at the Capitol's north steps is scheduled to follow late Friday morning.
"This is about letting the people of West Virginia have some closure," Manchin said of the memorial plans. "This is a celebration as much as it is us mourning. It's a celebration for a life that was unparalleled. We are going to have something befitting this man."
But the lingering vacancy affects the Democrats' slim Senate majority, and possibly the fate of some pending legislation. Byrd, for instance, was among 61 senators to vote for that chamber's version of the proposed overhaul of U.S. financial regulations. His death throws further into doubt the prospects for the House-Senate compromise of that measure, sought by the Obama administration.
West Virginia has not had an open Senate seat since 1984, when voters chose then-Gov. Jay Rockefeller to succeed a retiring Sen. Jennings Randolph.
Manchin told AP he has considered what he wants in an appointee: someone who embraces the policies he credits with moving the state forward, and who can help "Washington listen to what we're concerned about."
"It about, 'How do we keep our state on a good, solid financial footing?"' Manchin said. "There's a lot that goes into this, an awful lot."
Manchin said he's already received unsolicited advice regarding a successor to Byrd, and expects to reach out to former governors as part of the process.
"I'm listening. I want to hear," Manchin said. "I just want to get everybody's input."
Secretary of State Natalie Tennant has concluded that the seat won't go before voters until 2012, what would have been the final year of Byrd's record-setting ninth term.
The state's chief elections officer, Tennant cited her review of conflicting state statutes on the subject and a 1994 state Supreme Court ruling that arose from a gubernatorial appointment late in an election cycle.
State Republican Chairman Dr. Doug McKinney said the party is reviewing Tennant's decision, but didn't have immediate plans to challenge it. On Tuesday, a spokeswoman for Democratic state Attorney General Darrell McGraw said the office is reviewing the decision to make sure it is legally sound and supported by case law.
Potential choices for Manchin include former state Democratic Party Chairman Nick Casey; his successor and former longtime Manchin chief of staff, Larry Puccio; Senate President Earl Ray Tomblin, D-Logan; the first lady; and Anne Barth, a veteran top aide to Byrd.