Sen. Saxby Chambliss (R-Georgia) dashed Democratic hopes for a filibuster-proof majority.

With the reelection victory of Georgia Republican Sen. Saxby Chambliss in a special election last week, hopes that Democrats would command a filibuster-proof 60-seat majority in the upper chamber next year were dashed.

The number 60 has attracted enormous attention because it represents the votes required to defeat a filibuster in the Senate — the dreaded tactic that allows opponents of a bill to kill it by debating it ad infinitum. If they had secured 60 seats Nov. 4, Democrats could have prevented Republican filibusters and had their way legislatively.

Illustration by: Matt Mahurin

But many experts on Congress have a message for Democratic leaders: The failure to get 60 members probably won’t matter.

“[It's] insignificant,” said Michael L. Mezey, political science professor at DePaul University. “There are very few straight party-line votes on cloture, on cutting off debate … This whole 60-Democrat argument has been really overblown.”

GOP leaders have used the filibuster with great success since 2006, when Democrats won a slim 51-49 advantage (including two independents who caucus with the Democrats) in the Senate. House Democrats passed a long list of party priorities — including slashing carbon emissions and protecting journalists’ rights — only to see the legislation filibustered to death by Republican senators.

The goal of picking up nine additional Senate seats in the November elections was a rallying cry for Democratic supporters eager to end what they saw as two years of GOP obstructionism. Chambliss’ win in Georgia means that Democrats, at best, could muster 59 votes next year. The Senate contest in Minnesota remains too close to call.

No president has enjoyed a filibuster-proof Senate majority since Jimmy Carter.

Many of the experts contend that the Democrats’ belief that securing 60 seats would have been the key to legislative success ignores the regional and ideological nuances that influence voting patterns on both sides of the aisle. So much media attention has been focused on the entrenched partisanship on Capitol Hill that it has been easy to forget the handful of moderates who frequently cross party lines on a wide range of controversial issues and determine legislative outcomes.

Sens. Olympia Snowe and Susan Collins, both Republicans from Maine, have a long history of bucking their party to support such Democratic causes as expanding health coverage and protecting the environment. Pennsylvania Sen. Arlen Specter is another moderate Republican who, in avidly supporting government-funded stem cell research, has defied the Bush administration. Specter has also voted with Democrats on bills battling pay discrimination and strengthening workers’ rights.

There are others. Sen. John McCain (Ariz.) has backed Democratic bills to reform immigration policy. More famously, he was also the chief sponsor of a successful effort — wildly unpopular among Republicans — to limit the influence of campaign contributions in elections.

If these and other GOP moderates support him, President-elect Barack Obama could build early political momentum next year by putting together a string of big legislative victories.

Obama says he plans first to tackle an enormous economic stimulus package that would pump hundreds of billions of dollars into infrastructure projects and social programs. House Democrats passed a similar, though much smaller stimulus bill in September. It was killed in the Senate by a Republican filibuster, but Snowe, Collins and Specter all voted for it, as did moderate Minnesota GOP Sen. Norm Coleman, who might be back next year as well.

Even with 60 seats in the Senate, Democrats would not be assured of victories on everything. Connecticut Sen. Joseph Lieberman, an independent who tends to vote Democratic but became a pariah in the eyes of Democrats after endorsing McCain for president this year, has been a loud supporter of the Iraq war, voting consistently with Republicans against Democratic efforts to withdraw troops.

And Louisiana Sen. Mary Landrieu, a hawkish Democrat, has alienated many liberals with her votes on the war. Her push to expand offshore drilling in the Gulf of Mexico angered environmentalists.

The Progressive Patriots, a liberal group that rates lawmakers’ voting records, grades Landrieu a 19 — meaning she’s voted in support of progressive bills just 19 percent of the time.

This kind of cross-party voting undercuts the significance of a 60-seat majority for either party.

“On most issues, [Democrats] would have had to get some Republicans anyway,” Mezey said.

The current economic turmoil might help the party overcome its failure to secure 60 upper-chamber seats. Former GOP Sen. Lincoln Chafee (R.I.) said the deepening recession could force Senate Minority Leader Mitch McConnell (R-Ky.) and other GOP leaders on Capitol Hill to abandon their filibuster strategy for fear of alienating a public already angry at years of partisan bickering.

“The party’s discipline has been so strong, but with the country in such bad shape, I’m not sure that discipline can remain,” said Chafee, a visiting scholar at Brown University. “[Republicans] can’t keep losing seats. And if you look at 2010, I don’t see any vulnerable Democrats. They [Republican leaders] will probably have to change their behavior.”

One Republican who might become receptive to the Democratic appeals is Ohio Sen. George Voinovich, who faces reelection in 2010. With Ohio suffering disproportionately from the economic downturn, Voinovich has been one of the few GOP senators to jump on board the Democrats’ plans to bail out Detroit’s sputtering auto industry — a show of support that will likely continue if the economy continues to tank.

“Voinovich will be under a lot of pressure not to obstruct things,” Mezey said.

There are still weeks to go before Democrats can begin to enjoy their newly expanded Senate majority. As party leaders prepare this week to push through a bailout package for Detroit, some Republican opponents are already vowing to filibuster it.

Sen. Joe Lieberman (BiggerPictureImages flickr)

When Sen. Joseph Lieberman (I-Conn.) switched from Democrat to independent in 2006, Democrats needed him to remain in their caucus to control the Senate with 51 votes.

Yet many Democrats openly disdained Lieberman for championing the war in Iraq. The disdain escalated this year, when Lieberman campaigned tirelessly for Sen. John McCain (R-Ariz.), the Republican nominee for president.

It was something of a surprise, then, when a newly configured Democratic Senate caucus — no longer clinging to a one-vote majority — decided Tuesday, by a vote of 42-13, to keep Lieberman as one of their own. He will even retain his chairmanship of the Senate Committee on Homeland Security and Governmental Affairs, which is responsible for oversight of the executive branch.

Illustration by: Matt Mahurin

The vote appears to be less about Lieberman and more about Democrats and President-elect Barack Obama building a consensus. While highly critical of Lieberman’s straying allegiance, Senate Majority Leader Harry Reid (D-Nev.) was careful never to cut him loose. And Obama signaled that that he wanted Lieberman to remain in the caucus.

“The Democrats wanted to string up Lieberman by his toes and hit him with a broom,” said Kenneth Dautrich, a public policy professor at the University of Connecticut. “But by extending this olive branch, they’ve learned to overcome their emotional response and not be vindictive.”

“The result of the vote is not because the Democrats want to forgive him,” said Dautrich. “It’s because he’ll be an important vote.”

The 55-member Democratic Senate caucus — including at least five newly elected members — also allowed Lieberman to hold onto his chairmanship of an Armed Services subcommittee. But it stripped him of his chairmanship of a subcommittee of the Environmental and Public Works Committee.

After the caucus meeting, Lieberman said the vote “was done in a spirit of reconciliation.”

The vote came after 11 months of Lieberman stumping for McCain. The Arizona Republican even wanted Lieberman as his running mate before GOP strategists persuaded McCain to choose Alaska Gov. Sarah Palin.

That didn’t stop Lieberman from delivering a speech at Republican National Convention exalting McCain and blasting Obama.

“Sen. Obama is a gifted and eloquent young man,” Lieberman said in his Sept. 3 address. “But eloquence is no substitute for a record — not in these tough times. In the Senate, he has not reached across party lines to get anything significant done, nor has he been willing to take on powerful interest groups in the Democratic Party.”

Two days after Obama won the presidency and Democrats widened their margin in the Senate, an aide to Reid told the Associated Press that Lieberman would likely lose his chairmanship of the homeland security committee. Reid himself told a CNN reporter that, “Joe Lieberman has done something that I think was improper, wrong — and if we weren’t on television, I’d use a stronger word of describing what he did.”

The statement made headlines but Reid also hinted at reconciliation. “Joe Lieberman votes with me a lot more than a lot of my senators. He didn’t support us on military stuff, and he didn’t support us on Iraq stuff. But you look at his record — it’s pretty good.”

Then last week Obama informed Reid that he held no grudges toward Lieberman and wanted him to remain in the Democratic caucus.

“Once Obama intervened on this, it made it more likely that Democrats would treat Lieberman gently,” said Thomas Mann, a senior fellow at the Brookings Institution.

Julian E. Zelizer, a history professor at Princeton University, praised Obama’s support for the Connecticut independent as consistent with the president-elect’s calls for post-partisanship. “The Obama strategy of wanting to keep broadening his coalition is genuine,” Zelizer said. “Obama’s aware of the political flack he’ll take. But it’s a pragmatic move. He’s a non-ideologue.”

With Lieberman in the fold, the Democrats still have an outside shot of a 60-member caucus that could end Republican filibusters. That possibility hinges on yet-to-be decided races in Georgia and Minnesota.

“Lieberman will be a senator until 2012,” said Dautrich. “In the next four years, there will probably be votes on health-care reform legislation and Supreme Court nominees. … The Republicans will try to filibuster and the Democrats will need 60 votes.”

Lieberman, a senator since 1988, has had a rocky relationship with Democrats since he lost to Ned Lamont in the 2006 Democratic primary in Connecticut. After declaring himself an independent, Lieberman went on to defeat Lamont in the general election. He vowed to continue to caucus with Senate Democrats.

His chairmanship of the homeland security committee was largely viewed as both a reward and an incentive to prevent his defection to the GOP.

But the same issues that cost Lieberman in the Democratic primary also made him an oft-criticized chairman, especially his unflagging support of the Bush administration’s strategy in Iraq and overall “war on terror.”

It is unlikely that Lieberman will provide tougher oversight of an Obama administration that has welcomed him back into the Democratic Party.

“Lieberman is a very calculating politician,” said Zelizer. “I don’t think he wants to spend his political capital on investigations.”

Lieberman is thus expected to tread carefully. Thanks to the new configuration of the Senate, he needs the Democrats at least as much as the Democrats need him.