Sheehan was arrested in March outside the U.S. Mission to the U.N.
Actress Susan Sarandon joined Sheehan at a Mother's Day rally.
Public opposition to the war in Iraq reached a crescendo in 2006, fueling a backlash against the Bush administration and the Republican Party in the congressional midterm elections.
But throughout the fall election season, the "peace mom" who played a large part in launching the anti-war movement was comparatively silent. Cindy Sheehan has been largely absent from the political stage in recent months.
Now up for debate is whether Sheehan marginalized herself with her left-wing politics, including her photo op with Venezuelan President Hugo Chavez last January, or was dropped by the fickle media or was just unable to rebound from repeated attacks from conservatives.
From Sheehan's perspective, it doesn't matter. She may be yesterday's water cooler buzz, but she says she takes sober satisfaction that the November election proved she was not the only one disgusted with the war in Iraq and what it is doing to the country.
"I just read today that seven out of 10 people want the troops to come home in less than six months," she told FOXNews.com in a recent interview, talking from a cell phone while holiday shopping.
"I don't think I'm marginalized or out of the mainstream anymore. I think I'm right in the middle of the sentiment of most of America," Sheehan said.
Sheehan said her critics had done their best to ensure she stayed on the fringe, but it matters little to her now.
"If I lived my life according to what Sean Hannity and Rush Limbaugh said about me, I would just stay in bed all day," she said.
Just 16 months ago, in August 2005 Sheehan was in the middle of a large, rancorous media circus outside President Bush's ranch in Crawford, Texas. Adopted as "Camp Casey," named for Sheehan's son who was 24 years old when he was killed in Iraq in 2004, the protest site drew thousands of supporters, including actors and members of Congress, to a month-long demonstration in which Sheehan unsuccessfully demanded an audience with the president.
Though Sheehan had met with Bush along with other military families in 2004 and was quoted at the time as being satisfied that the president had felt pain for their loss, she later said that the meeting had left her "disgusted" with him.
The attention she stirred in Crawford did not get her a second meeting with Bush, who instead issued a statement and sent National Security Adviser Stephen Hadley and Deputy White House Chief of Staff Joe Hagin to speak with Sheehan during the standoff.
Hurricane Katrina put an abrupt end to the theater. Bush left his vacation at the ranch and Sheehan joined the group she founded, "Gold Star Families for Peace," and other anti-war activists for the "Bring Them Home Tour" that traveled across the country.
Political observers say Sheehan, called a gadfly, a leftist and even a "nut" by her detractors, quickly became old news. Her unpolished comments to the media often put her on the defensive.
She was ejected from the State of the Union address in February for wearing an anti-war T-shirt and was arrested in March in a protest outside the U.S. mission offices at the United Nations. Still, she no longer retained the persistent headlines of the Camp Casey days.
"Over that [August] month, the media followed every word she said, and then she's like an alien. I don't get it," said Leslie Kagan, director of United for Peace and Justice, one of the big anti-war organizations staging marches and protests since the invasion of Afghanistan in 2002.
John Gizzi, political editor for the conservative Human Events magazine, said such fickle treatment is hardly rare in political culture.
"When you're a media maven for a while you can be very appealing, you can be 'good copy,' as they say in our business, but you can eventually wear out your welcome," Gizzi said. "When you reach the point of being over-used, overexposed or over the top, you are quickly cast aside."
Others say Sheehan didn't fade, but burned herself out of the scene by her own actions. They cite her January trip to Venezuela, where she joined Chavez in criticizing Bush and agreed with activist actor Harry Belafonte that the president was the most dangerous terrorist in the world. That earned the scorn of even "Daily Show" host Jon Stewart, hardly a fan of the Bush administration.
"She turned out to be an imperfect grand marshal for the anti-war parade," said Ellis Henican, columnist for Newsday and a FOX News contributor. "Even those who are staunchly against the war sometimes look at Cindy and see a bit of a whack job."
Others insist that Sheehan remains an authentic voice against the war, one who, as a mother who lost a son in Iraq, has put herself out there at the expense of her private life and reputation.
"Cindy Sheehan is the real thing," said Dave Johnson, a fellow at the Commonweal Institute in California and founder and contributor to the SeeingtheForest blog. On the war in Iraq, Johnson said, "Cindy Sheehan was right. The people who marginalized her were wrong."
Philip Baruth, a novelist and political commentator who runs the VermontDailyBriefing blog, said Sheehan joins the ranks of individuals who come from left field to break ground on an issue only to be sidelined by more establishment voices once the issue is embraced by the mainstream.
"If you look at Crawford, that is where the [anti-war] debate was joined," he said. "I have unending respect for [Cindy Sheehan] … and other people who are able to pull their party and reposition the debate, but that often comes at the expense of their own media image because they are attacked so heavily."
Sheehan said she doesn't mind that she and the movement don't get credit for helping shift and embolden public opinion ahead of the election. She added that she is also disheartened that Democrats don't seem to be pursuing an exit strategy from Iraq now they have the power and mandate to do so.
"I don't think the Democratic leadership is reflecting what we voted for and voted against on November 7th," she said. "We still have to be out on the street, pushing them to do the right thing."