Massachusetts Gov. Mitt Romney plans to announce his decision to join the growing pool of 2008 White House contenders in early January.

But operations around Romney, including a private event on Saturday night that raised $9 million for his Commonwealth PAC, sure look headed in that direction.

The millions of dollars Romney has raised have helped pay for extensive travel around the country and donations to candidates in presidential states such as Iowa, New Hampshire, South Carolina and Michigan. He has won over activists and organizers from 43 states and 50 prominent CEOs, including the chiefs of Ebay and Marriot Hotels. His fundraising team also features nearly three-dozen Pioneers and Rangers from the Bush-Cheney election team. Those Bush backers individually raised $100,000 and $200,000 in each of the last two presidential campaigns.

Romney, 59, has also assembled some key GOP advisers and fundraisers. They include former Bush Justice Department spokeswoman and GOP adviser Barbara Comstock, longtime Gov. Jeb Bush aide Sally Bradshaw and former New York Rep. Rick Lazio. Alex Castellanos, one of the most sought-after GOP advertising men in the country, and Alex Gage, the Bush re-election team's voter microtargeting specialist, are signed on as well.

Romney and his family hosted an invitation-only conference in Boston over the weekend with a tour and dinner at Fenway Park. According to sources, Romney's family was enthusiastic, even "active participants," in what looked to be pre-run positioning for a White House run that included many words of thanks to the 150 participants.

Asked of his plans, Romney said he is "planning on making my decision sometime after the holidays." Romney is hosting his five sons, their wives and his nine grandchildren for Christmas at his vacation home in Deer Valley, Utah.

His term as governor expires Jan. 4, and a decision could be announced any time afterward.

Already, Romney, a Mormon, is trying to stake out ground as the conservative option in what could be a crowded Republican field. Romney opposes gay marriage and wants the Massachusetts high court to let voters decide state policy with a ballot question defining marriage as a union between a man and a woman. Ten days ago state lawmakers refused to approve the referendum. Romney is suing.

"This week, we will file an action before the courts calling upon the Judiciary to protect the constitutional rights of our citizens to vote," he said Sunday, adding, "I was struck by the irony and hypocrisy of our legislators so energized to protect the newly-discovered right to marry for some citizens had no compunction whatsoever about tramelling the long-established constitutional right of the people to vote."

Known as smart, conservative and charismatic, Romney has already won the respect of potential 2008 rival Newt Gingrich, who suggested the current field, including Sen. John McCain and former New York Mayor Rudy Giuliani, is missing a true conservative.

"There's a yearning for a clearer voice of conservatism and I think that Mitt Romney has an opportunity to fill that," Gingrich said on "FOX News Sunday."

But Romney's faith will be a real test for religious conservatives. Mormonism, or the Church of Latter Day Saints, has a complex and controversial reputation that Romney has often been reluctant to discuss.

In a Wall Street Journal interview in June, he briefly broached the subject.

"If you examine some of the history or practices or doctrines of a church you'll scratch your head and say, 'Boy, that sounds strange,' and that's certainly going to be true in mine and any other," he was quoted saying.

Senior White House correspondent for The Washington Examiner Bill Sammon spoke with Romney in September about his faith.

"He said, 'Look, I believe in Jesus Christ as my personal savior, etcetera, etcetera, etcetera,'" Sammon said. "I think that's the kind of talk that starts to win over some of these skeptical evangelical Christians. I think he's got that rap down pretty well ... But when I spoke to him today, this afternoon, what I think is interesting was he was essentially characterizing himself in so many words as the real conservative on the Republican side of the presidential hopefuls," Sammon said.

Deep theological differences divide Evangelical Christians and Mormons. But Tom Minnery, spokesman for Focus on the Family, an influential Evangelical Christian organization led by James Dobson, said Romney, who opposes abortion rights, has a bigger problem with flip-flops than with faith because of his support for abortion in the 1990s.

"Pro-life people have been observing politicians for long enough now to sense a little bit of nervousness about politicians who are late-blooming believers in the pro-life cause, as he appears to be," Minnery said.

Christian conservative voters are indispensable to a Republican presidential campaign and a little bit of quote nervousness is how many feel about Romney's religion.

"Nobody really knows how Mormonism will play across the board from the big picture once he gets on the national stage and starts articulating his faith," said Charmaine Yoest, Vice President of Communications for the Family Research Council.

FOX News' Carl Cameron contributed to this report.