Every decade or so, an electoral wave sends a new generation of politicians to Congress, injecting life and energy into stagnant legislative and policy realms. Such has been the case for the class of Republicans elected in 2010. Their zeal, and the GOP's control of the House of Representatives, has driven much of the Washington debate over the last two years.
More quietly, an infusion of new Democratic blood is happening at the same time, especially in the Senate. And while Republicans loudly proclaim President Obama to be the most liberal president of their lifetimes, he'll be gone after the 2016 elections. The younger generation of Democratic senators may prove the real source of the party's long-term liberalization.
The amount of turnover in the Senate in recent years has been historic. More than half the Senate -- 56 members -- began serving after the 2006 elections. Thirty-one of the 54 Democrats in the upper chamber took their seats, either by election or by appointment, in the past seven years. Among those in the newer ranks, seven are under 50 years of age, and another 16 are between 50 and 60.
The influx of newer, younger members comes at a moment of stark ideological contrast among generations. Younger Americans are much more likely to back gay rights and environmental protection than older Americans, while the rapid growth of Hispanics means younger Americans are more likely to favor sweeping immigration reforms.
To a degree, liberal interest groups that have long fought to persuade even Democratic members of Congress to see issues their way see the changing of the Senate Democratic guard breaking for their issues. The younger members, the thinking goes, are more likely to have been formed by their childhoods in the 1960s and 1970s, rather than the more traditional 1940s and 1950s.
"We've seen such a shift in environmental thinking over the past several decades that it's just much more likely that these issues have been formative with younger politicians," said Navin Nayak, a senior vice president at the League of Conservation Voters.
Environmental groups like LCV are more likely to get a friendly reception from Virginia Sen. Tim Kaine, Nayak said, than they would have from Jim Webb, the Democrat Kaine replaced. New Mexico Sen. Martin Heinrich is likely to lend a friendlier ear than his predecessor, fellow Democrat Jeff Bingaman, who had a long history supporting his state's mining interests. Chris Murphy, the Connecticut Democrat, will be a more reliable advocate for liberal causes than Joe Lieberman, the independent who caucused with Democrats but drifted away from the party's base in his later career.
Frustrated by the slow pace of Senate business, Sens. Michael Bennet of Colorado, Tom Udall of New Mexico, Mark Udall of Colorado and Jeff Merkley of Oregon, all serving their first terms in office, have been at the forefront of another pet project of the liberal base in reforming the rules of the filibuster. Older Democrats have been reluctant to change the rules, in part out of respect for a tradition of bipartisan comity that is now in short supply.
Gay rights groups, too, see the younger generation influencing their older colleagues. It was no mistake, one top aide observed, that so many Senate Democrats announced this year that they now support same-sex marriage after Obama and many of the new freshmen adopted the same position.
"There's no doubt that the younger generation of Senators, like younger Americans as a whole, are incredibly supportive of equality issues," Dan Rafter, a spokesman for the Human Rights Campaign, said in an email. "More than any other generation, younger Americans like Sens. Murphy and Heinrich have grown up counting LGBT people among their friends, family and neighbors."
This year, another wave of older Democrats are standing aside, and liberal groups see an opportunity to move Senate Democrats further into the post-Boomer generation. Sens. Carl Levin and Tom Harkin, both reliable liberal votes, are retiring; the two Democrats running for their seats, Reps. Bruce Braley and Gary Peters, respectively, have notched similarly liberal voting records.
In New Jersey, where Sen. Frank Lautenberg passed away earlier this week, the larger the number of candidates who enter the race for a special election later this year, the better for Newark Mayor Cory Booker, the front-runner at the moment.
In only one case will a younger Senate Democrat be in jeopardy of losing to an older member of his party. Hawaii Sen. Brian Schatz, 40, appointed to fill the seat left vacant by Sen. Daniel Inouye's passing, will face a tough primary challenge next year against Rep. Colleen Hanabusa, 62.
Such a changing of the guard is hardly rare in politics. New generations of Congressional Republicans arrived with Ronald Reagan's landslide victory in 1980, with the Newt Gingrich revolution of 1994 and with the Tea Party wave of 2010. The Democratic Year of the Woman, in 1992, ushered in new faces, and though many lost re-election bids in the 2010 wave, the classes of Democrats who rode anger at President George W. Bush to wins in 2006 and 2008 dramatically changed the face of the party's House caucus.
Just as the new crop of House and Senate Republicans have given conservative groups like the Club for Growth and the Heritage Action Fund a raft of new allies in Congress, so have the younger Democrats provided liberal groups with fresh avenues to work through. Together, the new generation will decide how Washington works, perhaps until the next generation rides in on another wave.