I don't have much patience with former Clinton flack Howard Wolfson's claim that Hillary would have been the Democratic nominee if John Edwards had been out of the race.
First, we don't know what would have happened if Edwards was out of the race. Al Gore could have jumped in or another candidate might have picked up momentum.
Second, we already know that almost anything can affect the outcomes of primary races, which have been shown due to be inherently unpredictable due to the role of momentum (voters shifting to support who they think is going to win).
Along the same lines, you can just as easily imagine multiple scenarios in which chance occurrences prevent Hillary from getting as far as she did. For instance, Bill Clinton's affair with Monica Lewinsky made Hillary a more sympathetic figure, pushing up her favorability numbers. If that affair doesn't happen, does she even reach the US Senate? You can play this game endlessly.