Over the last two weeks, I photographed both the Republican and Democratic national conventions. How do they compare?

John Brecher / NBC News

The crowds at the RNC, left, and the DNC, wait between speeches.

They're similar: there's cheering and pageantry, waving of signs, wearing of buttons, standing in lines, sweating in suits.

And, of course, they differ. Say "health care reform" to each crowd and observe angry disgust or relieved enthusiasm. The first arena cheers at Mitt Romney's speech when he says: "President Obama promised to begin to slow the rise of the oceans. And to heal the planet. My promise is to help you and your family."

And the next arena cheers for this line from Obama's speech: "…climate change is not a hoax. More droughts and floods and wildfires are not a joke. They're a threat to our children's future."

Concern for their children gets a rise from each audience. But it's what each group sees as a threat that determines which arena they stand in.

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At left, Mitt Romney accepts Republican Party's nomination to run for president. At right, President Obama delivers his acceptance speech at the DNC.

It's a bit like a huge sporting event in which the two teams play not at once, but in subsequent weeks. As pitched as their fervor gets, would fans really want the other team to stop playing?

Of course, it's not a game. Or rather, it is a game and also something far weightier: an huge nation taking shape, a great block of ideas and potential actions whittled into a form that a majority of its voters can support, or at least tolerate. 

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The vehicle at left drove around Tampa and Charlotte during both the RNC and DNC, while the street preachers at right worked at the center of Charlotte during the DNC.

For me, the best experience is to learn what motivates regular people who make the journey at their own expense. I'm especially curious about groups swimming differently in the stream, like the first national meeting of Mormon Democrats or Republicans for Ron Paul. Why do some women vote for Romney, or some senior citizens for Obama, when more members of those groups vote the other way? At both conventions, the attendees have one thing in common: they believe they're right.

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At left, Elliott Bell and John Michael Simpson sell Obama heads, t-shirts and buttons outside the DNC. At right, Nila Geiger attends a Tea Party event during the RNC.

See more visual coverage from the DNC in PhotoBlog and in this slideshow.

Or if you prefer, see the RNC in PhotoBlog and in this slideshow.

Slideshow: Twin sons of different parties

From tramping through cornfields to munching ice cream cones to holding babies – the time-honored traditions of the campaign trail leave President Barack Obama and GOP challenger Mitt Romney looking surprisingly alike.

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Nickie and Rodger Currie of Arlington, Va., sit in the upper deck of the Tampa Bay Times Forum as they  watch Mitt Romney deliver his speech at the RNC. "I think he hit it out of the park," said Nickie, because "he made it personal, and he showed his vision for the United States." Rodger said he's not personally driven to see Obamacare repealed, but he is very interested in reducing health care costs via effective policy, which he felt Romney alluded to.

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"Getting back into growth mode" is what James Patel of Edinburgh, Minn., thought was Romney's central message. "I like that he said that failed policies have us tucking our tail," said Patel, who finds hope in the message of growing business and making more use of domestic energy such as coal.

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"I enjoyed that he let his emotions come out. He let down his wall," said Shaye Leeper of Temecula, Calif., and her son Blake, 19. "Reaganesque," said Blake, pointing out that Romney referenced Reagan by asking if people think they're better off now than four years ago. "For people on the fence, that's an important question."

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John Brecher / NBC News

"I loved his speech," said Pepper Dombroski, of Maui. "It answered a lot of questions I had about him, and I've been following him for years. To me it wasn't just a speech for Republicans, it was for all Americans." She said he included a lot of comments directed toward women: "I thought he had a hopeful message for women in business and for stay at home moms. I don't know if it sounds the same to men, but when you hear those references it resonates."

At right, Dr. Mark Hartley of South Carolina carries out a souvenir as he leaves the Tampa Bay Times Forum, site of the RNC. As for Romney's speech, "I couldn't be more happy. Anybody who heard that speech, if they believe him, he'll be the next president. If they don't [like the speech], there's no hope."

More about Mitt Romney's speech:

• Romney accepts nomination, says 'The time has come to turn the page'
• Video: Romney accepts nomination
• Full coverage in NBC Politics
• More visual coverage of the RNC in PhotoBlog.
• Slideshow: The Republican National Convention

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As the Republican National Convention in Tampa builds to its final night and its most anticipated speaker Mitt Romney, take a spin through an interactive image, below, of the the Tampa Bay Times Forum where the events are being held. (Editor's note: This image was created by stitching multiple pictures together)

A view from the 3rd floor of the Tampa Bay Times Forum, taken between shows at the CNBC booth, one of many news studios ringing the floor. (John Brecher / NBCNews.com)

Workers, delegates, journalists and others mix and mingle as they pass through the hallway surrounding level 3 of the Tampa Bay Times Forum, site of the RNC. (John Brecher / NBCNews.com)

See more visual stories from the RNC in PhotoBlog, and NBC's full coverage of the event.

Slideshow: 2012 Republican National Convention

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"I like the idea that Mitt Romney is a businessperson, and is concerned about what's important to small business owners," said Kathy Eshelman of Columbus, Ohio. As the founder of a small business, Eshelman's main concern is the reinvigoration of the economy.

John Brecher / NBC News

Jane C. Edmonds, a professor at Northeastern University in Boston, is a Democrat who came to the RNC to offer her support for Mitt Romney's candidacy.

NBC's Michael O'Brien reported Tuesday on the Republicans' need to capture the support of women from Democrats, noting:

"Obama led Romney 51 percent to 41 percent among women in the August NBC News/Wall Street Journal poll, and the GOP brand lags significantly behind the Democratic brand among women voters."

 At the same time, there are thousands of women attending the Republican National Convention, and not all of them are Republicans.

At left, Jane C. Edmonds, a professor at Northeastern University in Boston, is a Democrat who came to the RNC to offer her support for Mitt Romney's candidacy. She served as secretary of workforce development for Gov. Romney in Massachusetts from 2003 to 2007 and says that experience convinced her that he'd be a good president:

"I want to be able to feel that the next president of the United States will be in a position to move us from the place that we're at right now to a better future."

John Brecher / NBC News

Mary Elizabeth Russell, who studies international political economy at the University of Texas at Dallas, holds her just-autographed copy of Dinesh D'Souza's "Obama's America" in the Channelside district of Tampa. She said about her presence at the RNC: "We're the first generation who's worse off than our parents, and that's what makes me want to get involved."

Siobhan "Sam" Bennett is president and CEO of The Women's Campaign Fund of Washington D.C., which provides money through its political action committee to female candidates of any party, provided they support abortion rights. Bennett says that though her positions on issues haven't changed in 30 years, her place on the political spectrum has shifted from moderate Republican to liberal Democrat.

John Brecher / NBC News

"I stopped believing you have to be a Democrat to effect change," said Anita Moncrief of Washington D.C., editor-in-chief of emergingcorruption.com. A former employee of ACORN, she voted for Obama but then became disillusioned with his administration's political appointments. She registered as a Republican in March after "two and a half years and a lot of soul-searching."

John Brecher / NBC News

"We probably don't really understand how good we have it," said Colorado blogger Michelle Morin about living in America. Morin's perspective starts with the idea that the United States is unique among nations because of the principles established by its Founding Fathers, and that the freedoms that make it special are subject to continuous erosion. She said: "Most Americans I talk to outside of the conservative movement don't really have a full understanding and grasp of those principles that made this nation great."

See more visual stories from the RNC in PhotoBlog, and NBC's full coverage of the event.

Slideshow: 2012 Republican National Convention

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Evan Vucci / AP

Ann Romney, wife of Republican presidential candidate, former Massachusetts Gov. Mitt Romney hands out cookies during a flight to Tampa, Tuesday, Aug. 28.

Eric Thayer / Reuters

A purse containing the latest issue of Time magazine, with Republican presidential candidate Mitt Romney on the cover, is seen during the second day of the Republican National Convention in Tampa, Florida ON Aug. 28.

Slideshow: Republican National Convention

Brendan Smialowski / AFP - Getty Images

Republicans gather in Tampa, Florida to officially nominate Mitt Romney and his running mate, Paul Ryan, as the party's candidates for the 2012 presidential election.

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From NBC's First Read:  The Ann Romney and Chris Christie speeches will try to accomplish these two different goals: the soft sell of Romney (which is Ann’s role) and the hard sell (which is Christie’s). In fact, you could argue that those are the dual themes of the entire convention. Ann Romney will attempt to humanize her husband, as well as try to appeal to women. Continue reading more on this story here.

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New Jersey Gov. Chris Christie talks with Joe Scarborough of MSNBC's "Morning Joe" on the floor before the start of the abbreviated first day of the Republican National Convention.

Slideshow: Chris Christie

Mel Evans / AP

The N.J. politician's straight-talk and tough policies put him in the national spotlight — but after considering a presidential bid, the governor decided he wasn't ready.

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New Jersey Gov. Chris Christie was swamped by journalists as he entered  the floor before the start of the abbreviated first day of the Republican National Convention at the Tampa Bay Times Forum in Tampa, Florida. The RNC is scheduled to convene today, but will hold its first full session tomorrow after being delayed due to Tropical Storm Isaac.  Gov. Christie will give his keynote address on Tuesday night. Christie is scheduled to appear tomorrow on Morning Joe with Joe Scarborough.

Full coverage

More photos from the Republican National Convention on PhotoBlog

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"We're not collectivists, we're individualists," says Tony Lanzetta of Port Charlotte, Fla., as he takes a break outside the Ron Paul rally in Tampa.

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Douglas Coggeshall of Palm Harbor, Fla., holds a Newt Gingrich sign he brought to the Tea Party-sponsored Unity Rally in Tampa. Though Coggeshall is firmly committed to Republican values, he considers Mitt Romney to be the wrong candidate to face President Obama.

John Brecher / NBC News

Linda Patterson, a Texas delegate from Grand Prairie, attended the Ron Paul rally in addition to her duties at the RNC. Regarding her political involvement, she said "I'm just an American who's said enough is enough."

Watch this video to hear what drives these and other non-mainstream Republicans to gather in Tampa.

• First Read: Republican National Convention in Tampa 
• Slideshow: Ron Paul

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