One of the nation’s largest tea party groups says it lost donations because the IRS refused to certify its status as a tax-exempt organization.

Donors “have generally said to us, when we get [IRS approval], come back and talk to us,” Jenny Beth Martin, the national coordinator of the Tea Party Patriots, told the organization’s supporters during a fundraising call Monday night. The call was intended to raise $20,000.

The group is now considering a lawsuit against the IRS, and may ask for damages, she said.

The IRS still hasn’t approved a formal tax-exemption for the Tea Party Patriots group, she said. Since 2010, “the IRS has been stringing us along,” she said, which has limited donations to the group and its small-scale political action committee.

“We’re dealing with years of not hearing anything back from the IRS or final approval or final rejection,” she said.

So far, the IRS has demanded the group provide it with emails, Facebook posts, all letters to members of Congress sent by supporters, and a list of donors, she said.

In response, the group hired lawyers and “gave them what we could without violating donor confidentiality,” she said.

Martin said the group has received donations from 400,000 people.

Other tea party groups gave up in the face of IRS demands for information that would be publicly released. “People in the IRS were .. abusing that position of power to intimated groups,” Martin said. “It scared some people [but] some continue to push forward,” she told the supporters listening to the conference calls.

During the fundraising call, the groups’ leaders repeatedly linked the IRS’ actions to the Democrats’ expansion of government into health sector via Obamacare and to the labor market via the immigration bill.

The proposed immigration bill is similar to Obamacare because it gives government far more power over people and companies, said Martin.

Under Obamacare, “we’re supposed to hand over our health information to government officials,” said Keli Carender, the group’s representative in Washington D.C.

Even though the IRS scandal is getting most news, “we can’t take our eyes off the amnesty bill,” Martin said.

The group is rallying its supporters against the immigration bill, which President Barack Obama recently lauded as “historic.”

The IRS intrusion “is what we expect out of banana republic,” said Carender, who also urged listeners to oppose the immigration bill. “We have repeatedly stood up against the consolidation of power by the elites,” she said.

“The IRS cannot be used as political weapon,” said Martin.

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