No worse than 2008 (D), possibly better. Remember how bad that was and how it went on for ever and ever. The result ended up being good.
I'm sorry, but this is complete and utter rubbish.
Despite some bitterness, Obama and Clinton were pretty much line-ball on issues and what they were doing was hardly isolating to Independent voters... this GOP nomination race is doing nothing but airing all of this extreme right-wing policies... and unlike the Dem race when there was some very left-wing stuff floating around... the candidates didn't publicly embrace them.
In 2008 the race unarguably made Obama and Clinton better candidates (mind you it was too late for Clinton) - each week makes Romney look weaker and weaker and his campaign is not responding.
In order to appeal to this bats*** GOP base, they've pushed themselves so far to the right and scrambling back to the centre is going to be incredibly hard.