Washington - The tradition-laden Senate voted Thursday to modestly curb filibusters, using a bipartisan consensus rare in today's hyper-partisan climate to make it a bit harder but not impossible for outnumbered senators to sink bills and nominations.

The rules changes would reduce yet not eliminate the number of times opponents - usually minority Republicans these days - can use filibusters, procedural tactics which can derail legislation and which can be stopped only by the votes of 60 of the 100 senators.

In return, the majority - Democrats today - would have to allow two minority amendments on bills, a response to Republican complaints that Democrats often prevent them from offering any amendments at all. The new procedures also would limit the time spent debating some bills and nominations, allowing some to be completed in hours that could otherwise take a day or more.

The changes were broken into two pieces and approved by votes of 78-16 and 86-9.

The two votes and a brief debate took less than an hour, impressively quick for the Senate. They came after a more typical day that featured a sprinkling of senators' speeches and long periods when the Senate chamber idled with no one talking, while private negotiations off the floor nailed down final details.

The pact leaves the Senate's minority party with far more power than it has in the House, where rules let a united majority party easily muscle through its priorities. It also falls short of changes Senate Majority Leader Harry Reid, D-Nev., had been threatening to ram through using the 55 votes Democrats have, a technique nicknamed the "nuclear option" because it is considered likely to produce harsh GOP retaliation that could grind work to a virtual halt.

"I'm glad cooler heads have prevailed here once again, and those who were clamoring for the nuclear option, most of whom have never served a day of their lives in the minority, didn't prevail," McConnell said in a written statement. He added that Republicans felt rules changes were not needed, merely a willingness by both parties to allow "vigorous debate and a robust amendment process."

Democrats say Republican use of filibusters has become almost routine and far too frequent. Republicans say they use it because Reid often blocks them from offering amendments.

The rules also don't go nearly as far as restrictions championed by a group of newer Democratic senators, such as requiring filibuster.

Even so, the agreement was remarkable in a period of bitter partisan clashes over President Barack Obama's budgetary, tax and social initiatives and GOP efforts to block them. It will streamline some of the Senate's work and avoid what could have been prolonged, nasty battling between the two parties if Democrats - frustrated by the GOP's growing reliance on the delays - tried forcing more decisive changes.

The No. 2 Senate Democratic leader, Richard Durbin of Illinois, said this week that Democrats lacked enough votes to force that proposal through the Senate.

Durbin said Thursday that the tentative deal was "great for the Senate," and said lawmakers who wanted tighter curbs would have to settle for less.

The deal gave each side something it wanted: Quicker action for Democrats, guaranteed amendments for Republicans. And it avoided clamping tight limits on filibusters that would alienate veteran lawmakers wary that their party could fall into the minority after any election.

Months ago, Reid said he favored completely banning filibusters when the Senate tries to begin debating a measure, a tactic Republicans have been using more in recent years. He threatened to use Democrats' strength in the Senate to enact that change and perhaps others by a simple majority vote, instead of the two-thirds majority most rules changes require.

Sen. John McCain, R-Ariz., among a bipartisan group of eight senators who proposed changes similar to those embraced in the deal, said the agreement showed that "it's possible for a group of us to join together on very difficult issues."

Tight restraints on filibusters were championed by less-senior Democrats like Sens. Jeff Merkley, D-Ore., and Tom Udall, D-N.M. They are frustrated with the chamber's often glacial debates and the ability of the minority - these days Republicans - to kill bills with less than majority support.

"Are they everything I want? Of course not," Udall said in an interview. But he said the Senate is "moving in the right direction. With these changes, it will make this a more efficient institution."

In an email to supporters, Merkley called the agreement an improvement but also complained that senators delaying legislation would not have to appear on the Senate floor.

"If senators want to force more debate, they should make their case before the American people so the public can weigh in on whether the filibusterers are heroes or bums," Merkley wrote.

The liberal group Common Cause, which has filed a lawsuit challenging the constitutionality of the filibuster, criticized Reid for the agreement, saying the senator "has gone missing in the fight for filibuster reform."

As part of the agreement, filibusters could be avoided when the Senate tries beginning debate on a bill or nomination. In return, the majority leader would have to allow each party to offer at least two amendments - addressing a major complaint of Republicans that their amendments are often shut out.

In addition, once the Senate votes to limit debate on certain nominations - district court judges and administration posts below Cabinet level - the debate would be limited to two hours, far below the 30 hours now allowed. The proposal was aimed at speeding the time spent on such nominations.

In addition, instead of three separate opportunities for opponents of a bill to wage filibusters to block a Senate vote allowing the chamber to try writing compromise legislation with the House, there would only be one such filibuster allowed.

According to the Senate Historian's Office, there were 73 "cloture" votes to end filibusters in the two-year Congress that ended earlier this month. There were 91 such votes in the Congress that served in the two previous years, and 112 in the two-year Congress before that. Republicans were the Senate minority party in each of those Congresses.

Those are the three highest number of cloture votes in any Congress since the Senate started allowing such votes to end filibusters nearly 100 years ago.