The much-criticized nomination of businessman George Tsunis to be U.S. ambassador to Norway is facing even more opposition, now from the co-chairs of the congressional Friends of Norway Caucus.

The co-chairs, Minnesota U.S. Reps. Betty McCollum and Erik Paulsen, are urging President Obama to withdraw Tsunis' nomination.

"In Minnesota we have a vibrant Norwegian-American population with a rich appreciation for the culture and heritage of Norway," McCollum said. "We expect the next U.S. ambassador to possess both expertise and appreciation for Norway and its people. Unfortunately, the current nominee falls far short of this standard."

McCollum, a Democrat, and Paulsen, a Republican, join both of Minnesota's U.S. senators in opposing Tsunis.

Tsunis, who helped raise nearly $1 million for Obama's 2012 campaign, was nominated nine months ago. During an appearance before the Senate Foreign Relations Committee in January, he bungled answers to questions and testified that he has never visited Norway. His performance drew a strong rebuke from Norwegian-Americans across the country.