John McCain announced in Dayton, Ohio, today that Alaska Gov. Sarah Palin, a 44-year-old conservative reformer, will be his running mate. Palin, who has been at odds with the state's unraveling Republican establishment, has been governor of Alaska since December 2006. Previously, she was mayor of Wasilla, a town with a population of 6,715.

A self-described "hockey mom" -- she has five children -- Palin enjoys strong support from the religious right and is a lifetime member of the National Rifle Association. She and McCain don't see eye-to-eye on every issue; she supports opening up the Arctic National Wildlife Refuge to oil drilling, and he, so far, has not.

"He has evolved, thankfully, in his thinking on offshore drilling," she said in an interview last month with Convention Daily. "When you consider his passion for national security, and his ideas on how to become less and less reliant on foreign sources of energy that are coming from in some cases some pretty dangerous, volatile regimes that are not friendly to Americans, I have faith that his thinking even on ANWR, development onshore, will evolve also into, to me, a more sensible plan."

McCain praised her today as someone who has been willing to "stand up to those who value privileges over responsibilities" and who has "an outstanding reputation for standing up to special interests" and fighting corruption. He didn't mention that those were intra-party fights, but he did speak approvingly of her as someone who reached across the aisle to get things done.

He said she "knows what it's like to worry about mortgage payments and the price of gasoline."

He noted that she is the daughter of a school teach and a school secretary, and was formerly a union member.

"She's got the grit, integrity, good sense and devotion to the common good that is exactly what we need in Washington today," McCain said. "She knows where she comes from and she knows who she works for."

"Sarah Palin is a pleasant surprise for those of us who had hoped that Senator McCain would pick a principled and authentic conservative pro-life leader, and Sarah Palin is," former Gov. Mike Huckabee of Arkansas said in a statement. "As a governor, she also brings an important balance of understanding of the critical domestic issues that is needed and that the Democrats have ignored in their ticket. Governor Palin is smart, authentic, tough, and a dynamic choice that will remind women that if they are not welcome on the Democrats' ticket, they have a place with Republicans."

Some Republicans were frustrated by the timing of Palin's selection and the secrecy surrounding it; she is virtually unknown to the rest of the country, and party operatives have not been able to prepare much information about her.

Palin ran as a Republican insurgent in a state where the entrenched Republican officeholders have been masters of pork-barrel legislation, exemplified by the so-called "Bridge to Nowhere." Sen. Ted Stevens, who was indicted this summer but won a primary battle for re-election last week, has been a regular target of McCain's scorn. Palin backed her lieutenant governor, Sean Parnell, in a primary fight against Rep. Don Young; the race was so close that no winner has been declared.

"It's just kind of some idiosyncrasies of some of the characters involved right now that frustrate me," Palin said last month. "They frustrate others. And we just need to clean house.

"I just happen to represent a demographic that the Republican Party had really better embrace and that is women voters, those very concerned about family, about safe, healthy communities so that we can raise our families in healthy manner. About energy independence, about national security issues. I just happen to be in a demographic that represents those values, those principles that we want to make sure that a president will give attention to."

Palin has been in a nagging controversy over the firing of her public safety commissioner, and whether it had to do with her desire to fire a state trooper involved in a custody battle with her sister. Matters weren't helped by the subsequent resignation of the new commissioner, amid charges of sexual harassment.

If Parnell wins the House seat, and Palin becomes vice president, the Alaskan Republican Party will likely fall into even greater disarray. Although Barack Obama's campaign has said it will be active in Alaska, the state has as little electoral significance to McCain as Delaware does to Obama.

-- Kirk Victor contributed to this story.