Census mails out more than three million of these surveys per year to American households. The surveys ask dozens of questions, including whether the home has a flush toilet, when people go to work, how much income they earn, and whether anyone living there has mental conditions.

"Isn't that lovely? The survey wants us to comment on the mental health of the people that live in the house," Poe said. "I'm glad my wife didn't get this survey and fill it out, talking about me.

"What's next? The government's going to start asking us how many guns we got in our home? What kind of cars we drive? Whether they're green cars or whether we're driving pickup trucks? Where's it going to stop?"

Failure to complete these surveys has lead to calls from Census, and even visits to people's homes to press them to fill them out. Poe recounted the experience of one of his constituents by saying Census officials were peering through the windows of her home.

"Where… in the Constitution does it give the federal government the authority to do this?" Poe asked. "The Constitution does not authorize peeping-tom-crats to come from the federal government to snoop around our homes and get information from citizens."

Republicans have also complained that Census has the authority to impose a $5,000 fine for non-compliance, although that fine is rarely issued.

Poe and Sen. Rand PaulRandal (Rand) Howard PaulPentagon: War in Afghanistan will cost billion in 2018 Overnight Finance: Senators near two-year budget deal | Trump would 'love to see a shutdown' over immigration | Dow closes nearly 600 points higher after volatile day | Trade deficit at highest level since 2008 | Pawlenty leaving Wall Street group Rand Paul calls for punishment if Congress can't reach a long-term budget deal MORE (R-Ky.) introduced legislation last year to make the survey voluntary. Poe's bill garnered 70 cosponsors in the House, and the House approved a version of that bill as an amendment to an appropriations bill, along with language that would cancel the survey altogether.

Poe is expected to reintroduce his legislation sometime today.

— This story was updated at 5:10 p.m. to correct the number of surveys sent out by Census.