On Capitol Hill, members of both parties saw the passing of Yuri V. Andropov as a possible opening for a new era in Soviet-American relations. ''I think it brings a chance to reexamine our relationship, and hopefully it will be different and better,'' said Senate majority leader Howard H. Baker Jr. (R) of Tennessee, who was among many urging unsuccessfully that President Reagan attend the funeral of the Soviet President.
''I don't believe that relations can deteriorate much further than they have now,'' said Sen. Charles H. Percy (R) of Illinois, chairman of the Senate Foreign Relations Committee.
Senate minority leader Robert C. Byrd (D) of West Virginia said, ''I hope the administration will signal the Soviets a serious desire to work with them in achieving reductions in nuclear arsenals and a lessening of global tensions.''
The change of leadership in Moscow offers a ''fresh start,'' according to Sen. Charles McC. Mathias Jr. (R) of Maryland, a member of the Foreign Relations Committee. But he added to reporters that ''in the short range I think it will mean relatively little.''
A collective leadership has been running the Soviet Union for some years, said Senator Mathias. ''It is probably capable of making decisions - like to break off the arms controls talks - and will continue to be a major influence for the immediate future.''
Mathias foresaw no effect on the arms race.
''The climate between the United States and the Soviet Union is so icy that I think until there are some other changes, there isn't likely to be arms control in the near future,'' he said.
Sen. Edward M. Kennedy (D) of Massachusetts said, ''This is a decisive turning point in Soviet-American relations,'' and added in a statement that it ''may be the last clear chance to halt that arms race.''
A more conservative voice, Sen. Dan Quayle, was less hopeful, especially on arms control.
The ''same conservative, hard-line bureaucratic leadership that first selected Andropov and then walked out of the (arms controls) negotiations will produce his successor,'' the Indiana Republican said.
Senator Percy said arms control progress is possible ''if new leaders are installed in Moscow who realize that it is not in their best interests to remain out'' of the talks.
Sen. Larry Pressler (R) of South Dakota, said, ''It was several months before the leadership succession question was settled after (Leonid) Brezhnev died in 1982, but Andropov's lengthy illness may mean they have had time to pick a successor who will begin to take charge sooner this time.''
Senator Pressler said he hoped that if a new leader emerges soon, ''there will be an opportunity for a face-to-face meeting between President Reagan and the new Kremlin leader that will break the logjam'' in arms negotiations.
Democrats tended to put much of the blame for arms control failure on the on President Reagan's hard-line stance with the Soviets.
Sen. Donald W. Riegle Jr. of Michigan, one of eight Senate Democrats who traveled to Moscow last summer, recalled, ''When we spoke with Andropov in August, he threw back at us much of the harsh rhetoric'' that he had heard from Mr. Reagan.
Saying that ''this is not an occasion for more hard-line rhetoric, but an olive branch,'' Senator Kennedy stressed that President Reagan should ''take the initiative without delay to move toward peace.''
While Mr. Reagan rejected advice to attend the funeral, voices on Capitol Hill are calling for him to meet with the new Soviet leader soon. ''The only way to break the impasse between the United States and the Soviet Union is to have a summit meeting,'' said Sen. Arlen Specter (R) of Pennsylvania.
As for the domestic impact of Andropov's passing, it is generally expected that uncertainty about the US-Soviet mood will benefit the incumbent President. However, one Democratic strategist argued that it might not help President Reagan or the Republicans.
''Anxieties are going to increase over the US-Soviet relations,'' said J. Brian Atwood, director of the Democratic Senatorial Campaign Committee.
The Soviet transition ''won't take away the anxieties,'' he said, adding that ''Democrats will be underscoring how dangerous'' the Reagan administration's foreign policies are.