Long written off by mainstream critics as an Islamophobic crackpot, Pamela Geller is winning increasing sums from financial backers with her blood-and-thunder warnings against the religion of Muhammad.

Geller is also having an undeniable impact on the national conversation about Islam.

The activist, whose anti-Islam event in Garland, Texas, was besieged by two gunmen, has, among other things, succeeded in galvanizing opposition to an Islamic cultural center near Ground Zero in Manhattan. She has also forced public transportation agencies in several cities to run her inflammatory advertisements, which denounce Muslims and Islam with a broad and largely indiscriminate brush.

In recent years, her actions have been taken under the aegis of the American Freedom Defense Initiative, which Geller co-founded in 2010 and which organized the Garland event.

The AFDI received almost $960,000 in donations in 2013, according to the group’s most recently available tax return. That’s up from $160,000 the year before and $19,000 the previous year, when the group was launched.

The steep increase in donations allowed AFDI to spend almost $400,000 in 2013, countering what it describes in tax filing as acts of “treason” committed by federal and state governments, the mainstream media and others “in their capitulation to the global jihad and Islamic supremacism… and the rapidly moving attempts to impose socialism and

Geller denounces Barack Obama as ‘a Muhammadan’ who ‘wants jihad to win.’

Marxism upon the American people.”

That same year, for the first time, the group was able to pay Geller a salary of almost $200,000.

Geller would not divulge the background of her main supporters. In an email to the Forward, she said, “We receive money from a large number of funders.”

The Forward did locate $100,000 of funding to AFDI given anonymously via a Jewish charity. The donations, received in 2013 and 2014 from a private donor or donors, were sent through Jewish Communal Fund, a donor-advised charity that allows the original funding source to direct where it wants its donation to go while masking its identity.

AFDI also raised almost $100,000 in 2013 and 2014 through four fund-raising campaigns on the crowd-funding website, Indiegogo.

One of the campaigns asked for money to mount a legal challenge to the British government’s decision to ban Geller from entering the United Kingdom in 2013. The other campaigns raised funds to pay for anti-Islam ads that ran in several U.S. cities on buses and in subways.

On her website, Geller has denounced President Obama as “a third worlder and a coward” who “will do nothing but beat up on our friends to appease his Islamic overlords” and as “a muhammadan” who “wants jihad to win.”

Her activities under the aegis of AFDI have led the Anti-Defamation League to criticize the group for “consistently vilifying the Islamic faith under the guise of fighting radical Islam” and for introducing “a growing number of Americans to [AFDI’s] conspiratorial anti-Muslim agenda.”

Geller conceded that her message is divisive to Jews, most of whom support tolerance toward other faiths.

“The Jewish community is divided,” Geller said. “For leftist Jews, liberalism is their g-d, and they have excoriated my work and defamed me. But many, many Jews have expressed immense gratitude for my work.”

Geller, a divorced mother of four from Long-Island, has come a long way since she launched a blog, Atlas Shrugs, in 2005 in response to the 9/11 terror attacks. The website’s name is a tribute to libertarian ideologue Ayn Rand, whose novel “Atlas Shrugged” warned of the dangers of a regulatory government.

She has been at the forefront of campaigns against an Arabic-language school in Brooklyn and against the proposed Park51 Islamic center that was to be located two blocks from Ground Zero in Manhattan, where the 9/11 attacks took place.

But it is her writing and speaking, on her blog, in books, at media appearances and at events, that have been most effective — and incendiary.

For more than 10 years, Atlas Shrugs has been a clearinghouse for the vilification of Islam. In it, Geller depicts Western society as ever on the brink of collapse. Judeo-Christian civilization is under constant attack from radical Islam. The imposition of Sharia law in Europe and America is never far away.

She and AFDI co-founder Robert Spencer were barred from entering the United Kingdom in 2013 and branded by the British Home Office as leaders of “anti-Muslim hate groups.”

Before the Garland shootings, AFDI was probably best known for running controversial ads on public transportation systems in such cities as New York, Boston and Philadelphia with messages like “Islamic Jew-Hatred: It’s in the Quran,” or, “In any war between the civilized man and the savage, support the civilized man. Support Israel. Defeat Jihad.”

Many city authorities rejected the ads. But with the help of an anti-Islamic lawyer, David Yerushalmi, AFDI prevailed on free speech grounds and forced city transportation agencies to run its ads.

In March of this year, Geller vowed to take out new ads on 100 New York City buses, naming and shaming big-name Jewish donors to the New Israel Fund, a group that Geller claimed, inaccurately, was a supporter of boycott, divestment and sanctions campaigns against Israel.

Geller called the donors, who include Saul Zabar, owner of a storied

Geller calls Jews who donate to the New Israel Fund ‘21st-century kapos.’

Jewish delicatessen in Manhattan, worse than “21st-century kapos,” a reference to Jews who enforced discipline on behalf of the S.S. in Nazi concentration camps.

Geller describes herself as a defender of free speech. Ten years ago she republished on her blog controversial cartoons of the Prophet Muhammad that were originally published in a Danish newspaper, sparking violent protests and death threats.

She staged the May event in Garland partly in response to the deadly terrorist attack by Muslim extremists on the offices of the satirical French newspaper Charlie Hebdo, which had also published images of Muhammad.

The AFDI event, held on the evening of May 3 at the Curtis Culwell Center, was an exhibit of entries to an AFDI-organized Muhammad cartoons contest. The group spent $10,000 on security for the sold-out crowd of more than 200 people.

Geller, Spencer and Geert Wilders, a Dutch anti-Islam campaigner who addressed the crowd, were unaware of the brief gun battle that raged outside during an ambush by two attackers armed with assault rifles.

The Islamic State group claimed responsibility for the attack carried out by Elton Simpson, 30, and Nadir Hamid Soofi, 34.

In late April, an ISIS supporter in Somalia, Mohamed Abdullahi Hassan, published a message on Twitter praising the Charlie Hebdo killers and calling on jihadi sympathizers in America to attack the Garland event.

Both Garland attackers were shot dead by a police officer. A security guard was shot in the ankle.

Authorities said there was little evidence to support ISIS’s claim, saying it’s more likely that the pair simply supported the group’s radical agenda.

Simpson was on the radar screen of counter-terrorism authorities for years. He was convicted in 2011 of lying to FBI agents about his desire to join violent jihad in [Somalia](file:///Volumes/English/To%20Production/javascript:loadEntitySearchResults(‘/search/entity?entityId=http%3A%2F%2Fd.opencalais.com%2Fer%2Fgeo%2Fcountry%2Fralg-geo1%2F391fbc5b-5081-b1ae-00b4-faaae91d3a58&sort=date&terms=). Soofi was a Pakistani immigrant who became disillusioned with life in the United States, friends said.

Geller said she has received many death threats in the past but this is the first time she has come under direct attack.

Even so, she said she would push ahead with another event showcasing caricatures of the Prophet Muhammad in the future. “We feel compelled to hold another event to demonstrate that we refuse to be silenced by violent intimidation,” she said.

Contact Paul Berger at berger@forward.com or on Twitter, @pdberger