If you began following U.S. politics during or just before Barack Obama’s first presidential campaign, you may not know how teeth-grindingly disappointing, how forehead-slappingly futile, campaigns and elections seemed to progressive observers in early 2003. The Iraq War looked unstoppable but hadn’t technically started; the boy king G. W. Bush was riding the slow-cresting wave of his post-9/11 popularity; wreck-the-government types had taken charge of at least one and arguably all three branches of government; and the man who had as good a claim as any to be an elected leader for the left, Minnesota senator Paul Wellstone, died in a plane crash ten days before the election, leaving his ballot replacement, the venerable Walter Mondale, to get beaten by the uniquely weaselly Norm Coleman. These results flipped control of the Senate, which had until then been the last apparent hurdle to a Washington where Dick Cheney’s word was law.

When the 108^th Congress assembled in 2003, just two new Democrats had defeated Republican incumbents. (Both are still there.) One was Long Island’s Tim Bishop, whose race was so close it was called only near Thanksgiving. The other was Chris Van Hollen, a former Maryland state legislator whose win was a radiant spot on a grim, gray night. Van Hollen upset Kennedy relative Mark Shriver to win the primary, in part because Van Hollen was able to show that he knew, and cared, about fine points of public policy. Montgomery County, Maryland, the bulk of Van Hollen’s Eighth District, holds government workers, lawyers, and plenty of scientists, all of whom tend to reward attention to detail. Those voters were no fans of W., but they were used to supporting Connie Morella, one of the last 1970s-era “liberal republicans.” Van Hollen defeated her almost without attacking her, insisting only that her presence enabled a GOP that had moved far to her right. 

Van Hollen was no Howard Dean, and he is no Obama: no national grassroots movement could form around him. Instead, he has become a model for other liberals in playing an inside game, helping run the institutions that keep the Democratic Party—and the federal government—around, while trying to shove it a bit to the left. Rarely confrontational in person, he “fit right in with all the smarty-pants” in his district, as one consultant said. He has signature issues, among them more rules about gun purchases, more disclosure about money in campaigns,...