Correction: An earlier version of this column incorrectly attributed a letter criticizing the “culture of misinformation” to Sen. Tom Udall. The letter was signed by Sens. Mark Udall of Colorado and Ron Wyden of Oregon. This version has been updated.

Last week, tea party-backed Sen. Rand Paul (R-Ky.) set the progressive world abuzz.

No, not with his usual retrograde positions on abortion, gay marriage or the Civil Rights Act of 1964 (he was against it before he was for it) — but rather with an op-ed in the New York Times, demanding that the Obama administration release its legal argument justifying the use of a drone to kill Anwar al-Awlaki, a U.S. citizen, without trial. Paul vowed to filibuster the nomination to the U.S. Court of Appeals for the 1st Circuit of former Justice Department official David Barron, who helped write memos supporting said argument.

Paul’s strong libertarian principles have always differentiated him from many of his Republican colleagues. It is, therefore, not all that shocking for him to speak out against a president he dislikes on a policy he disdains. Yet his outspokenness has many liberals and leftists asking a legitimate question: Why aren’t there more Democratic voices opposing the surveillance state? Protecting civil liberties should be a critical piece of the progressive platform, but too many establishment Democrats and progressives have been silent on this issue simply because one of their own is in the White House.

Some Democrats in Congress have taken bold stands. Longtime civil-liberties champion (and former House Judiciary Committee chair) John Conyers has worked to limit the National Security Agency’s collection of bulk telephone data. Reps. Keith Ellison of Minnesota and Adam B. Schiff of California have probed the administration’s drone and surveillance programs. Rep. Zoe Lofgren of California is pushing to prevent the NSA from weakening online encryption. In the Senate, Judiciary Committee chair Patrick Leahy of Vermont has held oversight hearings questioning excessive surveillance. Even Dianne Feinstein of California, chair of the Senate Select Committee on Intelligence and normally a committed defender of the intelligence community, finally spoke out after discovering that the CIA spied on Senate staffers. And last week, Sens.Mark Udall of Colorado and Ron Wyden of Oregon sent a letter to Solicitor General Donald B. Verrilli Jr., strongly criticizing a “culture of misinformation” that has resulted in “misleading statements . . . about domestic surveillance.” And Sen. Bernie Sanders, an independent from Vermont, has proposed a bill limiting FBI and NSA spying.

Still, too many Democrats and even progressives are reluctant to challenge the Obama administration, either because they don’t want to criticize a besieged president or because they’re focused on other priorities. As they stay silent, a host of troubling policies, including the assassination of U.S. citizens without due process, the prosecution of record numbers of journalists and whistleblowers, the unaccountable growth of the surveillance state and the vast expansion of the drone program, are proliferating unchecked.

To combat the spread of these policies, we need not just outraged rhetoric but also serious, concrete actions to seek accountability. And we need more progressive elected officials who are willing to fight for change.

We need leaders such as Shenna Bellows, who is running for the U.S. Senate in Maine. In her eight years leading Maine’s American Civil Liberties Union, Bellows has consistently worked across the aisle, bringing together unlikely allies to pass marriage equality, to restore same-day voter registration in the state and to make Maine one of only two states to establish cellphone privacy protections in the wake of the recent NSA spying revelations.

Bellows is an eloquent, vocal champion of progressive values across the board. But she is particularly focused on what she calls “the surveillance industrial complex.” “I just disagree on the amount of intrusion that is acceptable in our private lives,” she recently told MSNBC. Bellows wants to repeal the USA Patriot Act and release the CIA’s 6,000-page report on torture practices after the Sept. 11, 2001, terrorist attacks. She has expressed an interest in working with Paul and others on anti-surveillance legislation.

According to polls, Bellows has a tough race to unseat incumbent Susan Collins , a Republican. But she is leveraging her considerable organizing skills. And while Collins has vastly more money in her campaign coffers, Bellows — who recently earned belated support from Emily’s List and the Democratic Senatorial Campaign Committee — outraised Collins in the last quarter of 2013.

Bellows has been called “the woman who could be the future of progressive politics in America.” While this overstates the case, her unwavering commitment to civil liberties gives hope that progressives will soon have a champion who can help lead a transpartisan fight to rein in the national security state’s unconstitutional overreach.

Read more from Katrina vanden Heuvel’s archive or follow her on Twitter.