(CBS/AP)  In what is clearly the most important speech in her life, Palin went over her experience as a public servant.

"When I ran for city council, I didn't need focus groups and voter profiles because I knew those voters, and knew their families, too," she said.

Before Palin's big speech, vanquished Republican presidential hopefuls Rudy Giuliani, Mike Huckabee and Mitt Romney got enthusiastic greetings when they took turns speaking to delegates.

Giuliani, the former New York City mayor, praised Palin as "one of the most successful governors in America - and the most popular."

(Read the full text and watch the video of Giuliani's speech)

She's been governor for two years, after eight as mayor of tiny Wasilla, but Giuliani said she's ready for the vice presidency. "She already has more executive experience than the entire Democratic ticket," he said.

Giuliani was the early leader among Republican candidates in the presidential race, but he foundered quickly and quit the race without winning a delegate, endorsing McCain in January. Romney and then Huckabee did the same.

The McCain campaign had announced that Giuliani would be the keynote speaker at the convention, and he was to have spoken Tuesday night in that role. But the schedule was shuffled and most of its opening day was dropped because of the threat of Hurricane Gustav to the Gulf Coast.

Before Giuliani's speech, Mike Huckabee--another former governor who challenged McCain for the Republican nomination--took the stage.

Huckabee said that the heavy media scrutiny of the party, especially over Palin, had the effect of unifying the GOP. He said news media coverage has been "tackier than a costume change at a Madonna concert."

(Read the full text and watch the video of Huckabee's speech)

Republicans have been chafing over a wide array of questions that reporters have raised this week over the process by which Palin was vetted, her family and her record as a mayor and governor in Alaska.

The first of the three former McCain rivals to speak on Wednesday, Romney said Washington is dominated by liberal politics and asserted that people are tired of it. The Michigan native said the country needs change "from a liberal Washington to a conservative Washington."

(Read the full text and watch the video of Romney's speech)

Romney unsuccessfully challenged McCain for his party's presidential nod. The former Massachusetts governor said Wednesday night that the prescription for people wanting change is to "throw out the liberal government in Washington and elect John McCain and Sarah Palin."

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