Whether they voted for him or not, Americans are optimistic about the next four years with Barack Obama as president, according to a new CBS News poll. Seventy-one percent of all Americans say they are optimistic about the next four years, including nearly half (48 percent) of all those who voted for John McCain. Just 17 percent of all Americans are pessimistic, including 40 percent of McCain voters.Eighty-three percent of African-Americans are optimistic and 88 percent of Americans under the age of 30 are as well. While 88 percent of Democrats say they are optimistic, so do 51 percent of Republicans.During the campaign, Americans expressed record levels of dismay about the state of the country and the economy, and dissatisfaction with the current Administration. However, the level of optimism Americans now express about the future matches the level they expressed before many other recent presidents took office.About seven in 10 were also optimistic about Presidents Jimmy Carter, Ronald Reagan, George H. W. Bush, and Bill Clinton - before their first terms began. Six in 10 were optimistic in December 2000 about George W. Bush, even after that election's 35-day post-election struggle.