Remember Bush went from 54% of the vote in 1988 to 37% in 1992, despite having won a great Gulf War victory and despite the fact that 1992 economy was in recovery mode, this 3rd party effect created a harping on economy, making things sound worse than they were. Folks like Perot kept the election on the "issues" which was actually a way to create a smokescreen to hide Clinton's manifest character and honesty flaws, while creating a 'blame game' against Bush, made it easier for Clinton to sell his "its the economy stupid" message. Perot ended up being a stalking horse for Clinton. And lots of white male votes were drawn off by Perot.
Dole in 1996 was another story. That guy was such a horrible candidate he would have lost to a ham sandwich. And if the Republicans hadn't given up their spine in backing such a lackluster candidate they might have been much better able able to keep Clinton 'in check'.
Bill Clinton was/is a vile human being, but Republicans seem to forget that he was actually not a flaming liberal. He was more interested in his own gratification than in opposing the Republicans, and in fact passed a considerable number of Republican initiatives after re-branding them as his own.
Dole would probably have been a far worse President than Clinton should have been allowed to be (if the Republicans in Congress had had any spine), and may perhaps have been a worse president than Clinton in fact was.