The recent ad from Governor Romney accusing President Obama of waging a "war on religion" may be the first step in an escalation of religious rhetoric, according to Baylor University political science lecturer Andy Hogue. ABP News has more:

Hogue said the ad represents a shift away from what has been Romney’s major focus – the economy – to appeal to religious voters. Hogue said religion as a political issue had slipped beneath the radar since the primaries, when attention was focused on Romney’s Mormonism.

“Neither candidate has seemed eager to play up religion, but that truce wasn’t likely to last long, not with so much outside spending in this campaign,” Hogue said.
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Hogue noted that sparring over religion’s role in government became commonplace beginning in the 1980 election, when Ronald Reagan, Jimmy Carter and John Anderson charted new territory by appealing overtly to voters’ religious sensibilities and making public their religious commitments.

“We’ve seen that question posed, in one way or another, in every election since,” he said.

Hogue is author of Stumping God: Reagan, Carter and the Invention of a Political Faith.