WASHINGTON - U.S. Rep. Michele Bachmann, looking to boost her flagging presidential campaign, has turned to a longtime spiritual ally, Twin Cities Rev. Mac Hammond, to lead her outreach with the nation's evangelical community.

Hammond, senior pastor of Living Word Christian Center in Brooklyn Park, told his 9,000-member congregation Sunday that he is joining Bachmann's team, "working with her political campaign."

Hammond, audited by the Internal Revenue Service in 2008 after letting Bachmann speak at his Brooklyn Park megachurch, emphasized he is acting on a "personal basis" and not in his capacity as Living Word's pastor.

"Of course, my tightrope is this has to be done on a personal basis," Hammond said in a video of his remarks posted on the church's website. He noted that his church could not formally endorse her without jeopardizing its tax-exempt status.

Hammond preaches "prosperity gospel," which teaches that financial riches are the will of God for faithful Christians. He told his congregation that Bachmann has invited him to be chairman of a national faith and family council, but that he is still considering the "possible legal ramifications." He told the congregation he has been Bachmann's personal minister for some time.

Hammond said he has to be careful about his support for her because "the political opposition she faces is very poisonous." But, he said, he and his wife, Lynne, plan to travel with the campaign to "talk about the vital importance of the church rising up to take this nation back."

The Bachmann campaign did not respond to several requests for comment Monday.

Hammond's announcement comes at a time when Bachmann is trying to reignite the fire of her conservative evangelical base. On Wednesday she will speak at Liberty University, the Lynchburg, Va., Christian college founded by the late televangelist Jerry Falwell. Texas Gov. Rick Perry, a GOP rival with strong ties to evangelicals, spoke at the school earlier this month.

Hammond accompanied Bachmann on Friday to a gathering of several hundred pastors in Nashville.

Several groups that have challenged Hammond in the past said Monday they will keep a sharp eye on the pastor's involvement in the Bachmann campaign.

Barry Lynn, executive director of Americans United for the Separation of Church and State, said that after reviewing Hammond's sermon online, he believes the preacher is endorsing Bachmann from the pulpit.

"He's hedging his bets a little bit, but it's still clear he's endorsing Michele Bachmann from the pulpit. When he sermonizes about joining her political team, everybody knows he's just endorsed her," Lynn said.

Lynn's group filed a complaint with the IRS over Hammond's endorsement of Bachmann from the pulpit in 2006. After viewing Hammond's latest sermon, he said the group is considering lodging another complaint with the IRS.

Erik Stanley, an attorney for the Alliance Defense Fund, an Arizona group seeking to overturn IRS prohibitions against political activity by churches, said he believes churches "have a constitutional right to speak freely, and it's not the government's place to draw lines as to what a pastor can and cannot say from the pulpit." His group has been encouraging religious leaders to challenge the IRS by endorsing candidates openly in their churches.

Although critics have challenged the tax-exempt status of churches that endorse candidates, Stanley said other tax-exempt groups regularly engage in political activity, including labor and veterans groups.

"There will be eyes on him," said Melanie Sloan, executive director of Citizens for Responsibility and Ethics in Washington (CREW), a watchdog group that accused Hammond of endorsing Bachmann from the pulpit in 2006. "He's going to have to be very careful."

In campaign swings across Iowa and other states, Bachmann has been speaking regularly at Sunday church services about her own personal faith. While the talks are not explicitly political, they help her reach a potential constituency of small-dollar donors who have been important in her past fundraising efforts.

In his remarks online, Hammond said that "as a church we can't formally endorse any particular candidate, although, I might add, you know what the IRS policy is in that regard right now is under attack as being unconstitutional."

Hammond also told his congregants that while he's acting in a personal capacity, "if you're here, you're connected to me. We have an opportunity to make a difference in this arena of American life."

Not everybody was convinced at Living Word.

Eagan resident Norma Chappell, who attends Hammond's church, said she was put off by Hammond's remarks about Bachmann during his sermon.

"I don't want to know his politics," she said. "When you read the Bible, it was politics that killed Jesus. They killed him because of politics. And politics is dividing people now. We're supposed to be united as a people who represent Christ."

But Brian Sullivan, another Living Word pastor, said that the majority of the congregation seemed to accept Hammond's announcement. "He made it very clear it's him personally," Sullivan said.

Kevin Diaz is a correspondent in the Star Tribune Washington Bureau.