The singer-songwriter still must deliver a Nobel lecture in the next six months to receive his $927,740 prize.
The major Democratic donor's broadside underscores how the Minnesota congressman's campaign for party leader could erode relations with establishment Jewish groups.
Reform and Conservative Jews are asking the government to honor its commitments, writes the director of the Rabbinical Assembly in Israel.
Many Austrian Jews, one of Europe's smallest communities with 8,000 members, warned Hofer's popularity might lead the far right in Europe to a significant victory.
The couple also have a two-year-old daughter, Wyatt.