Senator Tom Harkin has tried repeatedly to change Senate procedures that obstruct simple majority rule. In January of this year, Senate Democrats failed to coalesce around his reasonable filibuster reform proposals, opting instead for what Harkin called “baby steps” that “don’t get to the heart of the matter.”

Tonight, while the chamber debated a low-profile bill, Senate Majority Leader Harry Reid used a simple majority vote to change Senate rules. He was targeting a procedure that amounted to a repeat filibuster rather than the filibuster itself, but he may have set the stage for major rule changes in the future.

Alexander Bolton reported the story for The Hill. The Senate was considering the Currency Exchange Rate Oversight Reform Act of 2011 and had just approved a cloture motion to end debate by a vote of 62 to 38 (roll call). Harkin voted with most Senate Democrats for cloture, while Chuck Grassley voted with most Republicans against ending debate.

Senate Minority Leader Mitch McConnell then tried to force a vote on a motion to suspend the rules so that further amendments could be considered. According to Bolton, “Republicans planned to use this right of the minority to embarrass Obama by showing that many Democrats do not support his jobs package as originally drafted.” (Some Democrats don’t like how the president proposed to pay for that jobs bill.)

Democrat Mark Begich was presiding over the Senate tonight and ruled that McConnell “does not need unanimous consent to force a vote on a motion to suspend the rules to consider amendments after cloture has already been approved.” But Reid considered McConnell’s motion a second filibuster, so he appealed the chair’s ruling. In a 51 to 48 vote (roll call), the Senate voted not to let the decision of the chair stand. In other words, McConnell didn’t get a second bite at the filibuster apple on this bill.

Grassley voted with all Republicans plus Democrat Ben Nelson to let the decision of the chair stand. Harkin voted with all the other Democrats present against the chair’s decision to let McConnell offer his motion without unanimous consent. Bolton comments,

The surprise move stunned Republicans, who did not expect Reid to bring heavy artillery to what had been a humdrum knife fight over amendments to China currency legislation. […]

The maneuver is arcane but momentous. If a simple majority of the Senate votes with Reid and strikes down the ruling, the chamber’s precedent will be changed through the unilateral action of one party.

Republicans had considered using this maneuver, dubbed the “nuclear option,” in 2005 to change Senate rules to prohibit the filibuster of judicial nominees. Democrats decried the plan and the crisis was resolved by a bipartisan agreement forged by 14 rank-and-file senators known as the Gang of 14.

Senate Republicans were furious at Reid’s actions.

“Just wait until they get into the minority!” one GOP staffer growled.

Note: filibuster reform advocates prefer the term “constitutional option” to “nuclear option,” since nothing in the U.S. Constitution indicates that a super-majority vote is required to change Senate rules.

Republicans are favored to win a majority of U.S. Senate seats in the 2012 elections. I wouldn’t be surprised to see a future GOP majority leader use tonight’s precedent to limit Democrats’ ability to use the filibuster. Elections have consequences.

Any relevant thoughts are welcome in this thread.