Barack Obama and Mitt RomneyJena Lee Nardella, a young Evangelical American who runs a missionary non-profit, stood at the convention lectern and prayed for one of the men running for president.

“May he know your presence, oh God, as he continues to serve as a leader of this nation, as a husband to Michelle and as a father to his daughters. Help him to see justice, love mercy and walk humbly with you.”

Nardella was animated in front of a crowd which was excited, if perhaps a bit surprised, to see her. She was speaking to the Democratic National Convention, and praying for Obama, offering an opening prayer many would have thought would be more in place at the conservative Republican National Convention the week before. Nardella proceeded to offer a similar blessing to Obama’s rival Mitt Romney, perhaps a consolation for the apparent incongruity of a member of the Republicans’ traditional core demographic, evangelical Christians, participating in a Democratic event.

Nardella’s appearance offered further evidence that those secularists who took the campaigns at their word when, earlier this year, they promised a religion-lite election cycle were going to be disappointed.

Nardella’s presence on the Democratic stage represents something that Democratic strategists and religion-followers alike have long known but frequently underplayed in public discourse: not all white, Protestant evangelicals are conservative. This is especially true of the so-called “Millennial” generation, evangelicals under 30. The devout demographic conventionally seen as belonging to the Republican Party is, in this election, up for grabs.

In fact if you analyse the stats it’s evident that the American religious population – i.e. most Americans – have historically split their loyalties between the two main parties. Black Protestant Americans, for instance, vote overwhelmingly Democratic. Currently mainline Protestants are about evenly split between Romney and Obama according to the latest polls from the Pew Forum. So are Catholics.

But white Protestant evangelical Americans hold a special place in the Republican Party’s idea of itself, in a way for which there is no Democratic analogue. To be sure, traditionally white Protestant evangelical Americans are heavily conservative and vote Republican in droves. But there are some big generational gaps opening up that confound the traditional political allegiances of that group. Younger, more socially liberal evangelicals are breaking with the previous generation’s politics.

A Pew survey from 2010, for example, found that 47 per cent of under-29 evangelicals believe the Bible is the literal word of God. This may sound high until you compare it to the percentage of all evangelicals who hold that belief: fully 60 per cent. Younger evangelicals are also more likely to support gay marriage than their older co-religionists. Demography is shifting the ground of religio-political America.

And yet, despite all this flux, both party conventions fell back into the old tropes. At the Republican convention in Tampa, Florida, speaker after speaker translated their conservative religious belief into predictable policy. They spoke with one voice on abortion (they’re against it) and gay marriage (against), and spoke up for “religious freedom”, Republican code for the right not to implement a provision of Obama’s healthcare reforms designed to provide women with access to free contraception. Because many Americans get their health insurance through their employer, religious universities and other institutions not considered churches (which are exempt) protest that they’d be forced to supply something they oppose on religious grounds. This unexpected resurgence of contraception into the public discourse on women’s health in the US has provided the Democratic Party with one of their more successful attack phrases for the election cycle, as they have warned of a Republican “War on Women”.

Meanwhile, despite Nardella’s prayer, the Democratic National Convention struggled to hit the right religious note, at least according to some of the more conservative watchers of political pageantry. Party leaders got themselves into a pickle by deciding first to drop a reference to “God-given potential” from their party platform – a non-restrictive but hotly discussed document that outlines the policies and priorities of the national political party – and then hastily reinstating it, apparently against the wishes of many of their delegates, or at least without the two-thirds majority called for in their constitution. The first move had them accused by delighted Republicans of the serious offence of “appeasing atheists”, the second led to accusations that the U-turn, although dressed up as expressing the personal position of the President himself, was in fact a cynical attempt to curry favour with the religious lobby. The debacle allowed conservative media website Brietbart.com, for example, to suggest that “The godless Democrats are now even more godless and no longer even trying to hide it.”

Unfortunately I missed the fun. As a religion-beat journalist on a budget I could only afford to attend one of the two conventions this election cycle. I didn’t have to flip a coin. Religion-spotting will always be better at the Republican Convention, so I headed to Tampa where 15,000 other journalists swarmed in the August Florida heat, which is something like standing in the steam of a just-opened dishwasher. We trudged through outdoor checkpoints, quarter-mile walks, endless quests for free outlets and a good signal, and a parade of parties and cloistered gatherings in which a heterogeneous party militantly insisted on its own uniformity.

Arguably, the Republicans had only one basic goal for this convention: to convince the American voting population that Mitt Romney was a viable candidate both for the party’s conservative base and for as many unaffiliated voters as possible. This was no small task. Of the dozens of delegates and guests I spoke to at the convention, especially at Tea Party and Religious Right-sponsored events on the fringes, not one identified themselves as an original Romney supporter. Most were Rick Santorum supporters, with a few Newt Gingrich loyalists. One man, trying to sell copies of his Cat in the Hat parody of the Obama presidency on the street, said he’d supported Michele Bachmann.

With so many delegates still loyal to candidates no longer in the running, organisers set about enthusiastically doling out “Mitt!” signs to the delegates on the floor as successive speakers lauded his character, devotion to family, and conservative cred. Wisconsin Governor Scott Walker – popular among conservatives – used Romney’s choice of the conservative Paul Ryan for his running mate as a springboard for his own praise of the candidate: “With this pick, he shows that the ‘R’ next to his name doesn’t just stand for Republican, it stands for reformer,” he said. “We need reformers. Leaders who think about the next generation more than the next election. That’s what you get from Mitt Romney and Paul Ryan.”

As Republicans tried to sell Mitt Romney to their own base, I was struck by how the rhetoric of the week was putting the “election” – the Calvinist idea of being chosen by God – into this election. With God on their side, Republicans handed over the agency of political change to righteous beliefs and divine intervention, with Romney as pastor for a broadly defined American congregation. Throughout the convention, as Romney and Ryan, Walker and Santorum were presented as potential party leaders, they were also anointed as the “elect”.

In Calvinist New England, church attendance was compulsory. But not everyone who abided by the law was considered a church “member”. That was reserved for the sanctified, for those who had demonstrated a sign that God had chosen them for salvation. This is how the Republican hypothetical church functions: the election that really matters is that of a divine nature, through which the party’s leaders are sanctified. Part of the appeal of this is that it allows Republicans to simultaneously trust their own political leaders (since they are chosen by God) while distrusting the whole institution of “government”, the realm of the unsanctified. This logic also carries a powerful message to the electorate: since Romney has already been chosen by God, who are you to go against that judgement?

Of course beneath the pious talk is a more profane reality: Romney’s primary rivals for the nomination didn’t lose because they were insufficiently sanctified, but because they were insufficiently financed. So at the RNC, wannabes and also-rans to the nomination competed for future economic sanctification by demonstrating their pulling power – get out the votes for Romney, and next time it could be you. Of all the failed primary candidates, Rick Santorum was particularly singled out as still sanctified, and a potential contender for 2016, due in no small part to his enthusiastic backing of Romney. At a Santorum-led rally to garner Tea Party support for the 2012 nominee, Romney’s son Matt returned the compliment, saying, “‘I have to say, we have a lot to look forward to in his career, don’t we?’”

The notion that a leader can both earn his place on the stage through hard work and possess inherent, divinely given qualities of leadership and judgement represents the peculiar intersection of religious election and American exceptionalism. It’s how a man as publicly rich as Mitt Romney can attempt to harness the power of conservative Christian grassroots “main street”activism without being laughed off the stage.

This is not to say that the Democratic Party plays it secular, either. The images of the Charlotte gathering showed something more akin to a tent revival than a political convention. Like Romney’s hard sell to his own party, President Obama faces a base somewhat deflated compared to 2008, when the rhetoric of “change” and “yes we can” mobilised so many voters. Both Obama and Romney face a similar challenge, to say “trust me” to a sceptical, anxious public. And both politicians have taken a similar approach, relying on a moral imperative to garner support. Obama’s base does not seem to expect the same unified stance on “correct” religiosity in the US, but, like Romney, Obama’s team attempted to paint the other option after November as not only less desirable but positively immoral. Obama and Romney need each other as enemies. Their reluctance to directly attack each other on religious grounds, i.e. their personal faith, is a concession to civility that cloaks, rather than reduces, the role of religious language in the 2012 campaigns.

Just after the Republican Convention Romney had more or less accomplished his mission of unification. But since then the unified party has taken a series of hits. Romney’s now infamous remark that he’s not worried about the 47 per cent of voters whom he painted as dependent on government has been followed by continued lukewarm performances in the polls, so much so that some conservatives have taken to re-weighting election polls, claiming a statistical liberal bias. Romney, by the way, uttered the harmful phrase at a private dinner for high-end donors to his campaign. A caterer secretly recorded the remarks, scraping off a layer or two of righteousness. These narratives have utterly overtaken those built at the conventions as attention turns away from mobilising the base and towards last-minute grabs for swing-state voters who might be vulnerable to a change of heart. Romney’s undisputed triumph in the first debate has certainly helped in this regard – gaining him up to 3 percentage points, according to some estimates – but swing voters, in the eyes of most analysts, remain undecided.

Which brings us to the central paradox of the role of religion in this year’s presidential elections. Religion is, for both parties, a cosmetic. Obama can mobilise the aesthetic of a tent revival to gear up his base for a repeat of 2008 while bringing in evangelical youths to attempt to poach from his rival’s stable of support. Romney’s campaign can use the language of election and conversion to explain why a formerly pro-choice, millionaire businessman who comes from a religious background many Christians would call a “cult” is the ideal candidate to represent them against an incumbent president.

But that cosmetic is covering some pretty deep imperfections. As the candidates move into the home stretch, religion could be a salve, a liability or of no consequence whatsoever. Neither party is going to lose their entrenched religio-demographic bases this election, so the battle is less about who the evangelicals will support, and more about how many members of the party’s fringe and base will opt to stay home this November.