Sen. Marco Rubio (REUTERS/Toby Melville)

Sen. Marco Rubio (R-Fla.) embarrassed Noah Mamet at his confirmation hearing, and now has delayed the campaign bundler’s move to South America.

Loop fans will recall that Mamet, a well-connected Democratic consultant who Obama picked to serve as U.S. ambassador to Argentina, admitted, when asked by Rubio in February, that he’d never been to the country. It was the type of gotcha question Republicans use to belittle political appointees headed to plum diplomatic posts.

(For what it’s worth, we have heard Mamet has traveled to nearby Venezuela, Mexico, Costa Rica and Chile.)

The Senate Foreign Relations Committee was scheduled to move Mamet’s nomination along Tuesday, almost four months after his confirmation hearing, but Rubio put a hold on it until the next business meeting. He’s only allowed to do this once.

We asked Rubio’s office – though we had a pretty good idea of the answer – why the senator requested the hold. His office referred us to this: