From Jeb Bush to Lindsey Graham: 2016 GOP hopefuls storm New Hampshire

The Republican Party's most ambitious have stormed into New Hampshire for an early state showdown that highlighted the diversity, political challenges and sheer size of the GOP's 2016 presidential class.

Nearly 20 Republican White House prospects were on the program for a weekend conference hosted by the state GOP, the year's first gathering of its kind in the first-in-the-nation primary state. Speakers on Friday ranged from the party's elite to its longshots: former Florida Gov. Jeb Bush delivered a standing-room-only speech while lesser-known South Carolina Sen. Lindsey Graham introduced himself to voters one at a time in the hallway.

Each contender offered prescriptions for a party that hasn't won a presidential election in more than a decade.

Bush made a passionate plea for bipartisanship on a day when his moderate brand of politics was on display. He broke with many conservatives on the environment by declaring that "the climate is changing" and on immigration called for a pathway to legal status for immigrants in the country illegally.

"The people who want to come here are driving for success," Bush said of such immigrants.

He also criticized those who demonize their political adversaries: "I'm sick and tired of the political game where you push someone down to make yourself look better."

He was among 10 prospective presidential candidates in New Hampshire on Friday, the first day of a two-day conference. Another 10 potential candidates were scheduled to appear in the state on Sunday.

Among the speakers: 10 current and former governors, three senators, a congressman, a former United Nations ambassador and a former CEO. They range in age from 43 to 71 and include several Spanish speakers and one woman.

Of the major candidates considering a 2016 run, only retired neurosurgeon Ben Carson did not attend the weekend conference. He cited a scheduling conflict.

"There's a new president coming, my friends," said New Hampshire GOP chairwoman Jennifer Horn, praising the diversity of the Republican field. "I'd like to also recognize at this time the broad, diverse, qualified field of candidates being offered by our friends in the Democratic Party, but I can't."

That's because the Democratic contest is dominated by Hillary Rodham Clinton, who launched her campaign earlier in the week. The 67-year-old former first lady and secretary of state is scheduled to campaign in New Hampshire early next week.

Just down the street from the Republican conference, a leading Democratic voice charged that all the Republican voices sound the same: "With all of their shared extreme views they might as well just be one," said Debbie Wasserman Schultz, chairwoman of the Democratic National Committee.

Yet divisions were on display among the Republican candidates.

"We're not going to fix Washington by electing a president who is from Washington," said former Texas Gov. Rick Perry, offering a jab at the members of Congress eyeing the White House. "Change is only going to come from the outside, from my perspective, and so should the next president."

And Bush said the United States must team up with other countries to fight climate change, a departure from the position of most rivals and many others in the GOP.

"We need to work with the rest of the world to find a way to reduce carbon emissions," he said. That won him praise from an unexpected quarter, Democratic billionaire environmentalist Tom Steyer, whose NextGen group issued a statement saying Bush demonstrated leadership on the issue and showed why "climate change doesn't have to be a partisan issue."

Florida Sen. Marco Rubio reiterated the need for a new generation of leadership. If elected, the 43-year-old Rubio would be the third youngest president in history. He launched his campaign earlier in the week.

Asked whether Rubio considers Bush to be a man from the past, Rubio avoided criticizing the governor who helped steer his early years in politics.

"It's not about biological age or how long someone's been in politics, it has to do more with the age of your ideas," Rubio said. "Do you have ideas to move America into the 21st century?"

Associated Press writers Holly Ramer, Kathleen Ronayne, Jill Colvin and Julie Pace contributed to this report.