Most of the delegation is attending the interfaith services here today re: the attack on the Boston marathon.
And if they can vote absentee for 'extreme' circumstances only, who gets to decide? The party leaders? The proponents of the bill? The opponents?
Feingold is the only one that sticks out in my mind as bucking this trend - he never missed a single vote, even as he was losing his 2010 re-election campaign and his opponent was working the campaign trail every day.
Unfortunately, people like Feingold are the exception, not the rule.