A conservative senator, not Democratic leaders, are to blame for the middle-of-the-night votes on healthcare legislation, Sen. Mary Landrieu (D-La.) asserted Sunday.

Landrieu blamed Sen. Tom Coburn (R-Okla.) for forcing late-night votes on the Senate's healthcare reform bill, a schedule which Republicans have universally criticized as an attempt to obscure attention to the bill.

"There's only one reason we're going to be here until Christmas, and that's Sen. Tom Coburn," Landrieu said during an appearance on CBS's "Face the Nation."

Coburn had forced a reading of a lengthy amendment from Sen. Bernie Sanders (I-Vt.) last week in a bid to slow down the health debate. Senate Minority Leader Mitch McConnell (R-Ky.) employed a similar tactic on Saturday, forcing clerks to read the entirety of the manager's amendment submitted by Majority Leader Harry Reid (D-Nev.).

Additionally, Republicans have signaled that they would exhaust the allotment of debate time scheduled for the bill, which is one of the factors forcing the 1 a.m. vote on Monday morning on the healthcare bill. A vote on final passage for the bill is scheduled for Christmas Eve, though the GOP will likely seek to throw that off-pace as well.

"We don't have to vote in the middle of the night, but he's the one making us do it -- not Harry Reid, not the Democrats," Landrieu added. "It is a Republican obstructionist that is making us vote in the middle of the night."

Update, 1:10 p.m.: A Senate GOP leadership aide shot back: "Maybe if Landrieu spent less time swindling taxpayers for special deals and more time paying attention to Senate rules, she’d know that the Majority leader is the one who schedules votes.”