At last count, at least 14 Democratic congressional candidates. The Washington Examiner has an editorial about the Democrats who aren’t coming, writing that:

Whatever excuses they offer, these incumbent Democrats are making a decision that often presages a party’s failure. In 2008, five incumbent Republican senators with competitive races skipped their party convention in Saint Paul, Minn. Four of them lost in that year’s Republican bloodbath as John McCain lost the presidential contest to Obama. Our searches for noteworthy Republican incumbents who stayed away from the then-popular George W. Bush’s renomination in 2004 turned up only Florida Gov. Jeb Bush, who was not facing re-election and (more importantly) had a hurricane running through his state the week it was held.

Interesting, to says the least.