ST. PAUL, Minn.  — Buffeted by revelations both political and personal, Republican vice presidential candidate Sarah Palin was presenting herself to the GOP convention Wednesday, even as John McCain’s campaign declared heatedly it was time to stop questioning her background. McCain was heading for St. Paul to be nominated in a roaring roll call.

McCain was “itchin”’ to get to the convention city, campaign manager Rick Davis said.

After a slow start of the convention because of Hurricane Gustav, momentum was building on Day Three of the GOP gathering. The spotlight was on Palin, the 44-year-old governor and surprise pick to be McCain’s running mate. She has been the talk of the convention, but most Americans have hardly heard her voice, let alone her views.

She will give her address in prime time, at 10:30 p.m. EDT.

“She will speak as a governor, a former mayor and someone with both hands on the steering wheel of America’s energy economy,” said Tucker Eskew, a senior McCain adviser. “She will make the case for Sen. McCain as the only candidate who has fought for America and the best man to protect us in dangerous times.”

First, the campaign lashed out at the media and called for an end to questions about Palin’s background and her family. Senior campaign adviser Steve Schmidt decried what he called a “faux media scandal designed to destroy the first female Republican nominee” for vice president.

“This nonsense is over,” Schmidt declared in a written statement.

Palin’s experience — she has been mayor of tiny Wasilla, Alaska, and has served as the state’s governor for less than two years — has been questioned since McCain chose her last week. The process that led to her selection has been criticized as hasty because McCain had met her just once before he offered her the job.

Palin also is the subject of an ethics investigation involving the firing of the state’s public safety commissioner after he wouldn’t dismiss her former brother-in-law, a state trooper. Her efforts as mayor to gain millions of dollars in federal funding through the so-called “earmark” process appeared to be at odds with the McCain message of fiscal reform.

Her personal life became a topic of discussion after Palin revealed that her 17-year-old unmarried daughter was pregnant. Yet her candidacy has excited Republicans at the convention and across the country, in part because she has earned a reputation for taking on entrenched interests in Alaska and is staunchly pro-gun and anti-abortion.

“Give her a chance to make her first speech, give her a chance to do her first interview,” said former New York Mayor Rudy Giuliani, the convention’s keynote speaker.

“Of course it’s going to be high stakes,” Giuliani said in an interview Wednesday with “Good Morning America” on ABC. “The media is ready to pounce on any mistake. ... She looks to me like she’s got tremendous confidence, got tremendous ability as a speaker.”

Palin walked onto the spare stage at the Xcel Center about 6:20 a.m. local time for a run-through and spent about 10 minutes looking out into the nearly empty arena and discussing where she would stand at the lectern and where she would look during her prime-time speech. Joining Palin were McCain campaign manager Davis and senior adviser Nicolle Wallace.

The disclosure Monday that Palin’s daughter Bristol is five months pregnant — and a continuing drip of potentially embarrassing details — knocked the convention off message before a rousing program Tuesday night.

Speakers extolled McCain as a war hero and maverick senator while blasting Democrat Barack Obama as an untested liberal. The 47-year-old Illinois senator is seeking to become the first black president.

“Democrats present a history-making nominee for president. History-making in that he is the most liberal, most inexperienced nominee ever to run for president,” former Tennessee Sen. Fred Thompson said as delegates roared with delight.

Palin, who has been in St. Paul since Sunday but out of sight, has a chance Wednesday to speak above the media din and present herself directly to voters as a strong-willed reformer and a solid conservative with appeal to women, including supporters of failed Democratic candidate Hillary Rodham Clinton.

The convention returned, mostly, to normal Tuesday after its opening session was cut short as Hurricane Gustav bore down on the Gulf Coast. With damage from Gustav relatively light, the political speeches began, with President Bush calling McCain “ready to lead this nation.”

Thompson, a longtime ally of McCain whose own campaign for the White House flamed out early this year, tossed chunk after chunk of rhetorical red meat to the delegates.

“Washington pundits and media big shots are in a frenzy over the selection of a woman who has actually governed rather than just talked a good game on the Sunday talk shows and hit the Washington cocktail circuit,” Thompson said.

But the media focus on Palin’s difficulties won’t go away, particularly since Bristol Palin and the unborn child’s father, 18-year-old Levi Johnston, were to attend Wednesday’s session. Republicans across the party defended Palin.

“I haven’t seen anything that comes out about her that in any way troubles me or shakes my confidence in her,” said former Arkansas Gov. Mike Huckabee, who ran unsuccessfully for the party’s presidential nomination this year.

The prime spot in Tuesday evening’s lineup went to Connecticut Democratic-turned-independent Sen. Joe Lieberman — whose vote presently gives Democrats control of the Senate — who enthusiastically endorsed McCain and Palin.

“When others wanted to retreat in defeat from the field of battle, when Barack Obama was voting to cut off funding for our troops on the ground,” Lieberman said, “John McCain had the courage to stand against the tide of public opinion.”

Jim Manley, a spokesman for Senate Majority Leader Harry Reid, D-Nev., said Lieberman “can give all the partisan speeches he wants, but as the American people have made very clear, the last thing this country needs is another four years of the same old failed Bush-McCain policies of the past.”