TOPEKA, Kan. -- National anti-abortion groups promise a vigorous fight if President Barack Obama nominates Kansas Gov. Kathleen Sebelius as U.S. health and human services secretary.

Abortion foes said Friday an important issue is a reception Sebelius once had with a late-term abortion provider who's now facing criminal charges.

Administration officials disputed the idea that abortion is an issue as to whether Obama nominates Sebelius. She is considered a leading candidate for the HHS job, although the White House has said others are being considered.

Abortion opponents acknowledged Friday that they'll probably be uncomfortable with nearly anyone Obama nominates, but they're particularly upset by the prospect of Sebelius.

A major reason is an event in April 2007 at the governor's residence with Dr. George Tiller and his Wichita clinic's staff. Abortion foes eventually obtained photos from the reception and posted them last year on the Internet.

"This is a whole different level," said Susan Fani, spokeswoman for the Catholic League for Civil and Religious Rights. "That someone who's so radical on this issue could be chosen is mind-boggling to us."

At the time of the reception, Tiller was under investigation by the Kansas attorney general. He's scheduled to go to trial next month in Wichita on 19 misdemeanor charges of violating state restrictions on late-term procedures, allegations he denies.

"It's not just that she has a pro-abortion rights viewpoint," said Charmaine Yoest, president and chief executive officer of Americans United for Life Action. "It's her very close association with one of the most infamous abortionists in this country."

Aides have noted that Sebelius has not received campaign contributions directly from Tiller since September 2001, before she officially kicked off her first campaign for governor.

Spokeswoman Beth Martino said Friday that Tiller purchased the right to attend the reception at a fundraising auction for an abortion rights group. Also, Martino noted a drop in Kansas abortions, which were 9 percent lower in 2007 than in 2002, the year before Sebelius took office.

Ron Pollack, executive director of Families USA, a health reform advocacy group supporting Sebelius, said he doubts abortion or the Tiller reception will be major issues for Obama.

"They both believe that they want to do whatever they can to minimize abortion," he said. "But they want to follow the rulings of the Supreme Court, and that's the law of the land."

Last year, the Roman Catholic archbishop for northeast Kansas said Sebelius, who also is Catholic, should refrain from taking Communion until she publicly repudiated her support for abortion rights. She didn't respond publicly.