Colebrook, N.H. ? It is in the nature of politics and of New Hampshire that things should heat up just as they cool down.

Now the days are shorter, the evenings cooler, especially here in what is known as the Great North Woods. But the stakes are growing, the debates becoming hotter. There’s a new wrangler in the race, Gov. Rick Perry of Texas, and he’s the talk of many of the towns — the great hope for some, the great worry for others. And if you’re just an observer, you can conclude that in the great scheme of things he is a great American character one way or the other.

Already he has fulfilled every fear and hope, widening the definition of treason, thinking out loud about the fault lines in the global-climate debate, crowding others off the stage and, with the help of Rep. Michele Bachmann of Minnesota, out of the Republican race. It remains to be seen whether this political cycle will be the GOP’s to claim, but right now the Republicans are dominating the conversation. They have the passion and the sense of purpose. This summer their creed is ripped straight from Bismarck: “If there is to be a revolution, we would rather make it than suffer it.”

The miracle of the season isn’t that the Republicans are making a revolution, but that President Barack Obama is in the role of defender of the old order. He thought of himself as the man who, to crib yet another line from Bismarck, might not be able to see “God’s cards” but could at least “see where the Lord wishes to go” and “stumble after him.”

Instead, the president has merely stumbled, and how he went from the leader of the crowd outside the Bastille to the personification of the ancien regime is one of the great mysteries of the age. Indeed, his determination, offered last week, to try to recapture the offensive with a September speech only underlines the urgency that is gripping the Obama camp.

So even though all the talk right now is of Perry and Bachmann (and let’s not forget former Gov. Mitt Romney of Massachusetts, still the putative front-runner), the election is and always will be about Obama.

He’s not doing well by any reasonable and conventional measure — and that’s without considering the peculiar challenge he faces due to the erosion of electoral votes in states he took in 2008 but which, because of population changes, would provide a smaller payout in 2012.

Presidents have limped toward re-election fights before and prevailed. Harry Truman did that in 1948 against greater odds than Obama faced; who thought the Democrats could win a fifth consecutive race with the party split so badly?

The better example might be the Obama hero, Abraham Lincoln, who was no sure bet for re-election in 1864, with the Civil War still grinding on, vital questions about slavery still unresolved, and a former general running as a peace candidate for the Democrats. Truman and Lincoln became emblems for their respective parties by staying the course, an old political phrase revived by Ronald Reagan, who didn’t look like a cinch for re-election either at this stage of the 1984 campaign but who nonetheless won 49 states.

But many embattled presidents don’t make it to that second term. Two recent examples are telling. The one that makes Democrats cringe is Jimmy Carter, who lost to Reagan in 1980 in an economic environment (deficits every year, frightening energy prices, high unemployment) that is arguably less severe than the one Obama presides over. The one that gives Democrats pause is George H.W. Bush, who was defeated by Gov. Bill Clinton of Arkansas as the deficit soared. Today the elder Bush, his health faltering but his uncommon chivalry still robust, is a bit of a bipartisan hero, and yet he left the White House after only four years.

Obama faces another challenge, perhaps the most ironic one of all. Since the Reagan years, passion has become an important element of American politics. Reagan was passionate about America; Clinton was passionate about changing the direction of both the Democratic Party and the nation; George W. Bush was passionate about revenge and security after the terrorist attacks of 2001 gave his administration and life new purpose and meaning.

Obama was passionate in the 2008 campaign, and anyone who was in a room or hall with him was rendered passionate by his performance. As president he has shown grace and intelligence, but he’s leaned toward the precise and away from the passionate, and it’s a strain to recall even a sentence he has uttered in the White House that can match Oscar Wilde’s goal of having “struck one chord to reach the ear of God.”

That’s why the ear of politicos twitched with fascination when, just the other day, Perry said, “I get a little bit passionate,” adding, “I think you want a president who is passionate about America — that’s in love with America.”

That one phrase may have been the most meaningful yet uttered in Campaign 2012, for it was a swipe at Obama’s cool demeanor even as it raised questions, so congenial to the hearts of conservatives and so galling to liberals, about whether the president isn’t more a critic of America than a defender of America.

Ironically, the Perry offensive has pushed Romney into the space that is also occupied by Obama: the cool operator acceptable to the old guard and to the very big money mandarins who are the personification of tea party resentments. Romney is no paladin of passion either — his best line from 2008 was when he playfully quoted his wife as saying that he wasn’t in her wildest dreams — and that could be a problem, both in his political profile and in his performance here and in Iowa.

A Gallup International poll taken this month shows the former governor with less “positive intensity,” which is a statistical concept but also part of the definition of a successful modern candidate. Bachmann and Perry lead the polls in passion. Romney leads the pack in money. The question this year, not only for Romney but for Obama as well, is whether money can buy you love. And whether passion counts.