http://www.chron.com/disp/story.mpl/ent/3607192.html Spoilers about the rest of the season: PASADENA, CALIF. - "Too close to call." That's how Josh Lyman sized things up at the conclusion of Sunday night's episode of The West Wing. The race between presidential candidates U.S. Rep. Matt Santos, D-Texas, and U.S. Sen. Arnold Vinick, R-Calif. a riveting race that has been playing out since last season had been leaning Vinick's way. But after a near-meltdown at a California nuclear plant, pro-nuclear Vinick has lost his grip on such key states as Florida and Ohio. The result: "Too close to call." Spoiler But what chance will Santos have if his running mate, Leo McGarry, should suddenly pass away? That is a story line that will play out during the nine remaining episodes of the show. On Sunday, NBC announced that the Emmy-, Peabody- and Golden Globe-winning series will end in May. Three of those nine episodes feature John Spencer, one of them prominently. Spencer, who died of a heart attack Dec. 16, plays McGarry. "We spent a lot of time during the Christmas holidays trying to figure out what we were going to do," executive producer John Wells said Sunday night. "We had conversations about whether it was even appropriate to continue to do the show without John. He was such a central part of the ensemble and of our lives together as a group." Unknown to most, Wells had already had a private conversation with NBC Entertainment chief Kevin Reilly on Thanksgiving. They had discreetly agreed that the show, suffering from anemic ratings, should come to an end. Wells kept that information mostly to himself. In huddles and e-mails with the show's other producers over the Christmas holidays, a decision was reached on how the series should proceed. Spoiler Five days before the election Leo will die, leaving Santos with a choice unprecedented in American politics, one without constitutional provision: how to deal with the death of a vice presidential candidate on the eve of an election. Santos will have to decide to either publicly reveal a last-minute substitute choice for his vice presidential running mate or go silent. If he's elected, he'll have to try to get his choice nominated and passed by Congress via the 25th Amendment. Producers briefly considered reshooting the unaired episodes in which Spencer appeared. They considered going in other directions. A report after Spencer's death suggested that in a September episode he had a scene set after the election. The producers checked and discovered Spencer wasn't seen in the future. So they decided to proceed with episodes he shot shortly before his death. "John was so wonderful in those episodes that the best homage we could make to his contribution to the show was to let people see the last days of his work," Wells said. The show will go on hiatus in February during NBC's coverage of the Winter Olympics. It will return in March. Spoiler The highly anticipated election episodes will air April 2 and 9, and as the series races to its finale, it will deal with a government in transition. The final episode, May 14, will show an inauguration. Whose inauguration? The producers and cast members are not saying. What is known is that efforts are being made to bring back characters from the show's seven seasons. There's a good possibility, for example, that Rob Lowe (Sam Seaborn) will take a final bow. Saturday, producers and cast members gathered for a private memorial service in Spencer's honor. At the service, some in the cast asked Wells about a press session scheduled Sunday. He told the cast to gather Sunday and all would be explained. Some knew and others had guessed, but on Sunday Wells made it official when he announced that a decision had been reached to end the series. Cast members there reflected on the passing of Spencer and the closing days of a landmark series. Proceeding without Spencer "is incredibly difficult," said Allison Janney (C.J. Cregg). "To be on that set without him, I feel a great loss. It feels like a very organic ending to the show with him gone, because I just can't imagine doing it without him." "John was the guy saying, 'This is phenomenal. Relish this.' He was always saying that to me," said Bradley Whitford (Lyman). "It's very hard to understand how somebody just goes away." For Martin Sheen, playing the role of President Jeb Bartlet ranks as one of the three standouts in his career, to go with his roles in the movies Badlands and Apocalypse Now. "We knew we had a special show," he said, "and we all knew as actors we were not going to get this opportunity again in our lives, particularly myself and John, because we were the oldest and we felt we had a great restarting or rebirth of our careers and maybe the most important parts of our lives. "Because we were the oldest, and I guess because we had so many similar experiences with our demons and had gone through so much of life and family and coming to grips with where we were with age and career, we felt like the parents to these wonderful children."