Senate Democratic leaders are seriously considering employing rarely used Senate rules against "dilatory" motions and amendments to thwart Republican attempts to drag out debate on health care legislation, several Democratic sources acknowledged. The move could be considered the Democrats' version of the "nuclear option," given it would likely be seen as a serious weakening of the minority's right to offer amendments on a bill that cannot be filibustered because it would move under special "reconciliation" rules. Senate rules prohibit dilatory amendments and motions once the chamber has broken a filibuster or invoked cloture, but there do not appear to be any specific rules pertaining to how many amendments or motions can be offered under reconciliation. However, Senate Democrats are likely to argue that reconciliation rules prohibit a filibuster, and that offering an endless stream of amendments is an attempt to get around that rule. One Senate Democratic leadership aide cautioned that no decisions had been made, but said, "While abiding by the rules of the Senate, we're prepared to do what we can to move the bill." Senate Republicans have made no secret of their plan to try to trip up the Democrats' strategy for passing a health care bill this year. That plan entails forcing potentially weeks of amendment votes both as an attempt to alter the bill and to stall a final vote. However, some sources said they doubted Republicans would have the stamina to force such a stretch of nonstop Senate voting, and that Democrats may never need to draw on the rarely used rules. The Democrats' strategy for clearing health care legislation would require House approval of a comprehensive health care measure the Senate passed on Christmas Eve. But because the Senate lost its filibuster-proof supermajority after that vote, changes demanded by the House would go into a second budget reconciliation measure that cannot be filibustered and requires only 51-votes for passage. That legislation also would have a 20-hour limit on debate. Votes on amendments, however, are unlimited, and previous reconciliation debates in the Senate have featured multiple days of nearly nonstop voting in what has become known as a "vote-a-rama." House and Senate Democrats have been aiming to complete the process before they leave for a two-week Easter recess on March 26. In order to cut off the Republicans' amendment strategy, sources said Democrats would likely allow voting on amendments to go on for a couple of days. Once it was clear the GOP amendments were failing routinely and intended to be "dilatory," Senate Majority Leader Harry Reid (D-Nev.) would appeal to the chair, which would be occupied by Vice President Joseph Biden — whose constitutional role includes serving as President of the Senate — to rule specific amendments out of order. Democratic sources said there is a well-established principle in the Senate of getting around delay tactics. One key precedent they point to is the 1977 fight over a natural gas regulation bill. At the time, Sens. Howard Metzenbaum (D-Ohio) and James Abourezk (D-S.D.) were mounting what was known as a "post-cloture" filibuster. The Senate had agreed, 77-17, to invoke cloture, or limit debate on the bill, but for 12 days and one full night the two Senators filed amendment after amendment, forced readings and demanded quorum calls. Then-Majority Leader Robert Byrd (D-W.Va.) called on then-Vice President Walter Mondale to rule 33 amendments out of order on a variety of bases. "I asked the Vice President to take the chair and rule on points of order — which I and other senators would raise — making various motions and quorum calls dilatory under cloture and peremptorily ruling amendments out of order on their face, (for example, as being incorrectly drawn or not germane), thus avoiding the endless roll calls that could otherwise consume weeks," Byrd wrote of the incident in his book on the history of the Senate. After that incident, Senate rules were changed to prohibit post-cloture filibusters. The rules regarding cloture now state: "No dilatory motion, or dilatory amendment, or amendment not germane shall be in order." Roll Call could not identify any precedents involving a reconciliation bill. Senate Republicans in 2005 came close to using their own nuclear option, in which they would have gotten then-Vice President Dick Cheney to rule that filibusters of judges are not allowed under the U.S. Constitution's "advise and consent" clause for nominations. The gambit was dubbed the "nuclear option" because of it's potential to ignite a partisan brawl that could have brought the chamber to a standstill.