Picking Ryan, 42, the Wisconsin congressman and House Budget Committee chairman, has helped immensely, as Romney and Ryan easily won majorities of the 2,286 delegates.
Former New Hampshire Gov. John Sununu, who served as President George H.W. Bushs chief of staff, formally nominated Romney. His state, which his son once represented in the U.S. Senate, is considered a swing state in November.
Were saddled with a failed presidency with an incumbent president who has not led, Sununu told a crowd that seemed more absorbed in conversation. He got little applause.
Sununu would pause, waiting for cheers that rarely came, with lines like, There are many reasons America needs Mitt Romney at the helm. Barack Obama cant figure out what makes the private sector work.
The mood Tuesday was sometimes businesslike, sometimes festive.
Before Ann Romney and Christie spoke, the speech that most got the crowd on its feet came from Artur Davis, a former Democratic congressman from Alabama.
There are Americans who voted for the president, but who are searching right now, because they know that their votes didnt build the country they wanted, Davis said. To those Democrats and independents whose minds are open to argument: listen closely to the Democratic Party that will gather in Charlotte and ask yourself if you ever hear your voice in the clamor.
Throughout the day and evening, delegates heard dozens of speeches sounding the same message and quietly adopted a party platform that Democrats are eager to attack.
That platform, when combined with the one Democrats are expected to adopt next week at their convention, will provide voters with the starkest ideological choice theyve had in a generation. A new Pew Research Center survey found more people were interested in the Republican Party platform than in Romneys Thursday night acceptance speech.
Some party leaders are concerned.
If it was up to me, Id put the platform on one sheet of paper. Have you ever met anyone who read it? asked House Speaker John Boehner of Ohio, the nations highest-ranking Republican, at a meeting with reporters. I would put it on one page so that the American people would read it. They might.
Democrats are focused, particularly on the section on abortion. We, however, affirm the dignity of women by protecting the sanctity of human life. Numerous studies have shown that abortion endangers the health and well-being of women, and we stand firmly against it, the platform says.
Romney has said he backs abortion in the case of rape, incest, or if the life of the woman is threatened.
Some delegates worried that the plank, which Democrats have been aggressively criticizing, could cause trouble throughout the fall.
It already has made it harder for us, and will until people wake up and stop bringing this up every four years, said Frank Simpson of Cumming, Ga., who runs a cheese company.
But Bill Drout, a Spring, Texas, software consultant, argued that voters would appreciate the partys stand on principle.
I dont mean to diminish the seriousness of the crime of rape, Drout said. We should make the penalties more serious. But either you believe life in life or you dont.
Bonnie Hersman figured that the platforms issues will be overwhelmed by less tangible factors. West Virginia voters go with their hearts in a presidential election, and they pick who moves them, she said.
Romney has never been a big favorite with conservatives, but many delegates said the addition of Ryan gave them new energy.
Im a lot more enthusiastic now that hes chosen Paul Ryan. Ryan knows the language of conservatives, said Jorge Landiver, an internet company owner from Arlington, Texas.
Democrats remained active during the Republican convention. Obama kicked off a two-day tour of college campuses Tuesday, his campaign downplaying questions about the propriety of campaigning during his opponents convention and with a storm nearing the Gulf Coast.
Before he left for the trip, Obama delivered brief remarks at the White House, telling residents in the Gulf to heed the warnings of local emergency officials. And he opened his remarks at Iowa State University by noting that it was important to say that our thoughts are with our fellow Americans down on the Gulf.
White House spokesman Jay Carney dismissed a question of whether the image of campaigning during a storm was bad, saying, The president is president every day, and noting that hed be getting briefings on the status of the storm and the federal response throughout the trip.
Lesley Clark of the Washington Bureau contributed.