A watchdog group filed a complaint Tuesday with the IRS against a Minnesota church, claiming the pastor violated the church's tax-exempt status by endorsing Republican congressional candidate Michele Bachmann.

An official from the church, Living Word Christian Center in Brooklyn Park, Minn., said Tuesday that the pastor misunderstood IRS guidelines and promised it wouldn't happen again. But the watchdog group, Citizens for Responsibility and Ethics in Washington, said it would not rescind the complaint.

Bachmann, who is running against Democrat Patty Wetterling in Minnesota's 6th Congressional District, told parishioners at the church on Saturday that God had called on her to run for Congress, according to a video of her appearance posted on YouTube by "Dump Bachmann Blog." She also said God is now specifically focused on her race.

When he introduced Bachmann, Pastor Mac Hammond said that the church could not endorse any candidate.

"But I can tell you, personally, that I'm going to vote for Michele Bachmann," he said to laughter and cheering, "because I've come to know her, what she stands for, and I want her to share her testimony with you tonight."

Under federal tax law, church officials can legally discuss politics, but to retain tax-exempt status, they cannot endorse candidates or parties in their official capacity.

According to a fact sheet the IRS puts out to help churches and other charitable organizations maintain their tax-exempt status, "leaders cannot make partisan comments in official organization publications or at official functions of the organization."

Hammond was not available for an interview Tuesday, but associate pastor Tim Burt said Hammond thought he was within the rules by saying he was speaking personally.

"When Pastor Hammond went to introduce her, he did make a comment of (personally) endorsing," said Burt, who confirmed the video was accurate. "He didn't knowingly or deliberately violate IRS guidelines. He misunderstood the IRS guidelines ... Pastor Hammond agrees that going forward, this is not going to happen again."

Melanie Sloan, the executive director of Citizens for Responsibility and Ethics in Washington, said that wasn't enough.

"They knew they were skirting the law," she said. "He knew exactly what he was doing. The IRS has been sending out guidelines to churches, to avoid exactly this."

In its complaint, CREW says it appears the church "illegally promoted" Bachmann's candidacy, and asked for appropriate fines and penalties, including revocation of the church's tax-exempt status.

IRS spokeswoman Nancy Mathis declined to comment on the complaint.

Bachmann's appearance and the possible violation of IRS rules were first reported Sunday by the left-leaning blog Minnesota Monitor.