now, nbc has responded tonight. they say they are disappointed and that they will work in good faith to try to resolve this, but all of this, also, comes at the same time this weekend on sunday, many of the campaigns will gather in washington to discuss how they can really join forces to push for changes in the next debate up. that's in just two weeks, wolf, on the fox business channel. >> there's another development. you're out there on the campaign trail right now with marco rubio. after being criticized. now, criticized for missing lots of senates votes and changed his campaign schedule showing up for an important vote overnight. what's the late effort ast on t? >> reporter: right, wolf. marco rubio just arrived in sioux city but cancelled and earlier event to show up for that 3:00 a.m. vote in washington against the budget deal. of course, in the midst of the scrutiny in him as a senator, hasn't showed up for many votes while running for president.