The lengthening list of Americans calling for more investigations of ExxonMobil Corp.'s behavior on climate change includes members of Congress, three presidential candidates, dozens of climate scientists and Glenda Poliner, a San Diego grandmother.

She was one of almost 9,000 people who signed a petition calling on California Attorney General Kamala Harris to investigate whether Exxon misled the public on global warming. Poliner, a schoolteacher who says she has a second grandchild on the way, included a note to Harris, a Democrat.

"I almost told my daughter to not have children because they would be facing a steadily deteriorating world because of the actions of companies such as ExxonMobil," she said in the note. "These companies must be held accountable for their misdeeds. Please continue to do everything in your power to reverse this devastation."

From the halls of Congress to the campaign trail to households across the nation, there is a roiling call for federal and state prosecutors to probe what Exxon knew about climate change and whether it broke consumer and shareholder protection laws in what it communicated to the public. Petitions and other public demands for investigations follow the publication of investigative stories by InsideClimate News and other news organizations that showed Exxon was at the forefront of global warming research decades ago until it launched campaigns to cast doubt on climate science and delay action.

Exxon is already the target of a probe by the state attorney general in New York, though the inquiry was opened months before the nationwide clamor for action began. Investigators for Democratic Attorney General Eric Schneiderman subpoenaed Exxon records last month spanning four decades of research findings and communications about climate change.

"We're not just shouting this into the wind," said R.L. Miller, president of the political advocacy group Climate Hawks Vote. Her organization called on U.S. Attorney General Loretta Lynch and California's Harris to open probes into Exxon.

Miller, a California environmental activist who is influential in the Democratic Party's environmental caucus, said she expects the party's California candidates for the U.S. Senate, including Harris, to make an investigation of Exxon part of their platform. Doing so would play a "very, very big part in the committee's decision on who to support," Miller said.

More than a dozen environmental and activist groups have mounted petition drives, including CREDO, the California League of Conservation Voters, Climate Hawks Vote, MoveOn, the Sierra Club, the Union of Concerned Scientists, Avaaz and 350.org.

"We're not surprised that Exxon lied about climate change," says a petition aimed at the U.S. Department of Justice that was fashioned by 350.org and circulated by a number of groups, including Climate Hawks Vote. "We're not even surprised they lied for so long. What's dismaying is that they just might get away with it." So far that petition has collected 355,000 signatures.

The California League of Conservation Voters petition signed by Poliner has attracted 8,934 supporters since Nov. 20. A petition orchestrated by the Union of Concerned Scientists has drawn 12,500 signers since Dec. 11.

Exxon declined to respond to questions.

A spokeswoman for Harris said the office does not comment on possible investigations. The U.S. Justice Department as a matter of policy "generally neither confirms nor denies whether a matter is under investigation," spokesman Mark Abueg said in an email.

"We suggest seeking clarification from the company and if it is willing to provide additional details," Abueg said.

Public demands for action and petition drives—no matter how impassioned—typically have little influence on how prosecutors proceed, said former California Democratic Attorney General Bill Lockyer, though such calls are never completely off the radar for elected officials.

"Prosecutors make decisions based on the best available facts, not on public opinion," Lockyer said. "But they have to remain open to listening. Now whether that goes from listening to prosecutorial action is another question."

Although the calls for investigations may not carry legal sway, they are raising social consciousness, said Stephen Mulkey, president of Unity College in Maine, which calls itself "America's Environmental College."

"There is so much awareness now about the conduct of Exxon that it is making it increasingly unlikely they can continue business as usual," said Mulkey, who led a successful effort to get the college to join with other educational institutions in selling fossil fuel investments such as Exxon stock. Even if Exxon is never hauled into a court of law, it faces a guilty verdict in the court of public opinion, Mulkey said.

"The voice of the public can be very powerful," Mulkey said. "They are saying it's time to take a stand."

U.S. Rep. Ted Lieu, a California Democrat, was one of the first to call for an Exxon investigation. Others doing so in Congress include Rep. Mark DeSaulnier, a California Democrat, and Sen. Sheldon Whitehouse, a Rhode Island Democrat.

Lieu, a former military prosecutor who is in his first term in the House, said that while investigators must act independently, the pressure being brought to bear is vital because it signals a national will to take action. He said he feels an obligation to the people of his Southern California district to press for an investigation.

"I believe one of my duties is to yell and scream on behalf my constituents," Lieu said. "When things go wrong—and it is very clear to me that things are wrong with Exxon—I have a moral obligation to speak as loudly as I can to bring light to the issue."

Lieu's two sons—Brennan, 12 and Austin, 10—are part of his motivation, he said.

"We have a moral obligation to make sure we give a world to our children that is better than we have now," he said. "This is about the future as much as it is about the past."

That's the message Lieu said he believes will resonate with those empowered to hold Exxon accountable. It's also the point that hooked Poliner, the San Diego grandmother and teacher.

"We're talking about the future of the world, something that will destroy our planet," Poliner said. "I can't think of anything that's more important."