He became known as a solo economic power in his home state as part of the Senate Appropriations Committee, where he steered federal money toward Hawaii to build roads, schools and housing.
Colleagues and aides lined the rotunda of the U.S. Capitol on Thursday to bid aloha to Inouye during a rare ceremony to demonstrate the respect he earned over decades.
He was eulogized by President Barack Obama.
Obama, who arrived early Saturday in Honolulu for his annual Christmas family vacation, said during a service at Washington's National Cathedral on Friday that Inouye's presence during the Watergate hearings helped show him what could be possible in his own life.
Visitors began signing condolence books at the governor's office on Friday, with additional books available at the Saturday service.
The service brought a steady stream of mourners toward downtown Honolulu one day before another service for Inouye was scheduled at the National Memorial Cemetery of the Pacific. Obama plans to attend that ceremony, White House officials said on Saturday.
Oskar Garcia can be reached on Twitter at http://twitter.com/oskargarcia.