It's one of those legislative showdowns where every vote could count and any vote not cast could be decisive.
Senate Majority Leader Harry Reid called Saturday for Hawaii's Democratic governor to appoint "with due haste" a successor to the late Sen. Daniel Inouye, then the body's most senior member, who died Monday at age 88.
"It is critically important to ensure that the people of Hawaii are fully represented in the pivotal decisions the Senate will be making before the end of the year," Reid said in a statement.
On the agenda: legislation to avoid part of or all of the fiscal cliff and emergency relief for the states hammered by Superstorm Sandy. Should Congress not act, a series of tax increases and spending cuts would go into effect in the new year.
Before he died, Inouye did something to help the process along: he named Rep. Colleen Hanabusa as his preferred successor.
Hanabusa is a first-term Democrat and represents the state's 1st congressional district.
Hawaii state law provides for Gov. Neil Abercrombie to appoint a temporary successor "by selecting a person from a list of three prospective appointees submitted by the same political party as the prior incumbent." The temporary successor serves until an election is held; the winner of the election serves the remainder of the original term, meaning Inouye's seat will be on the ballot in 2014 and 2016.
Abercrombie said in a statement: "The people of Hawaii deserve to be fully represented in the debates and decisions the Senate will have on those matters in the coming days and weeks."
The law requires the successor to have been a member of the former Senator's party -- in this case, a Democrat -- for at least six months and a resident of the island state.
Abercrombie sent Democratic Party Chairman Dante K. Carpenter a letter formally requesting three names be submitted.
The party has 21 days to provide the list, but does not appear to be waiting the full three weeks. It set a Monday deadline for applications.
Should the list go to the governor and successor be named promptly, the new senator could be in Washington ready to be seated when the Senate returns December 27.
Inouye will be buried on Sunday at the National Memorial Cemetery of the Pacific. President Barack Obama, who is spending the Christmas holiday in Hawaii, will be among the attendees.
The state's other representative, Rep. Mazie Hirono, was elected in November to fill the seat of retiring Sen. Daniel Akaka.
Sen. Jim DeMint, R-South Carolina, has announced he will retire in January, but has not yet vacated his seat. Gov. Nikki Haley said she will appoint Rep. Tim Scott.
Massachusetts Sen. John Kerry is also expected to resign his seat in the new year. Obama has indicated he will nominate Kerry for secretary of state, and Kerry is likely to be confirmed by his Senate colleagues.