There’s a lot of talk, most of it silly, about the dynamics at play as we head toward October in the presidential campaign. Maybe there’s virtue in cutting away a lot of the chaff by describing the state of play in a sentence: Voters are coming home, because events are nudging them there.

It’s about time. This is an important election, this is a symbolic election, this is a high-intensity election, this is a high-interest election. Until now it was also an odd election:

The Republican base, which since 1980 has included religious conservatives, was alienated; the nominee wasn’t one of their own, and had little affinity for them. The Democratic base, which since 1932 has included blue-collar and unionized voters, was equally unsettled; the nominee, though raised by a single striving mother, was struggling to reach these voters, who had been moved more deeply by Senator Clinton than by him.

Indeed, for most of 2008, the presidential campaign has been conducted under the political equivalent of a climatic inversion.

Senator McCain was talking about the evils of big business and its lobbyists, which first sent waves of shock and then waves of panic across the Republican pond. At the same time, Mrs. Clinton, for most of her time in the national spotlight a poster child for Ivy League elitism and upper-middle-class feminism, had transformed herself into a fighter-for-the-people in the Hubert H. Humphrey mold while Senator Obama, who was reared in far more gritty circumstances, found himself imprisoned in an image that cast him as a modern-day Adlai Stevenson, not quite sardonic but not quite a man of the people either.

That phase is over, and there are two reasons: Sarah Palin. Economic upheaval.

The selection of Ms. Palin brought an end to Mr. McCain’s problems with religious conservatives. Like President Bush, Ms. Palin isn’t merely appealing to religious conservatives; she is one. The press’s inquiries into Ms. Palin’s views and the airborne invasion of reporters into Alaska (target: Wasilla) may have sowed doubt among undecided voters but they removed any doubt among believers. Mr. McCain is now free to move about the country, unencumbered by worries about religious conservatives sitting on their hands. Those hands have been busy lately, applauding.

For the weeks following the selection of Ms. Palin, Democratic hands have been wringing in worry. There is no recent example of a presidential campaign being so flummoxed in the face of its rivals’ maneuvers; it was as if the Obama campaign had adopted radio silence.

That’s over, too. Just as the Palin nomination swept away all the pumped-up enthusiasm of the Democrats’ Denver stadium rally, the terrifying extremes of the markets and the rout in the financial sector of the economy — toppling some of the icons of Wall Street, diminishing others, transforming those that survived from investment bankers into commercial bankers — have placed the contretemps about Ms. Palin’s former brother-in-law on the news bridge-to-nowhere. Suddenly, it’s the economy, again.

That plays to Mr. Obama’s strength in November, even though the economy surely is not his strength personally (nor Mr. McCain’s, which doesn’t help the Republicans trying to flee the record of President Bush). Though Mr. Obama’s remarks on the economic tumult are only peripherally different from those of Mr. McCain — more emphasis on the homeowners who hold mortgages than on the financial institutions that own the mortgages, plus he’s talking about middle-class tax breaks as part of an economic-stimulus package — he is the principal beneficiary of the economic stress.

Mr. Obama has business bigwigs on his team and on his donor lists, to be sure, but his camp is emphasizing that the Democrats aren’t responsible for the mess, that the Republicans can’t clean up the mess, and that the mess isn’t going to go away unless Washington recognizes what Treasury Secretary Paulson and others are saying with their actions: The magic of the markets has its limits, and government has an important role to play.

This is good for Mr. Obama because suddenly he no longer has to worry about the traditional Democrats who voted for Clinton and shunned him in the primaries; few are likely to flock into Republican arms, even those held out at arms’ length (or more) from Mr. Bush. Much like Mr. McCain’s choice of Ms. Palin firmed up his support among religious conservatives, events have conspired to solidify Mr. Obama’s base and give him more elbow room as the campaign proceeds.

Both men now seem liberated — but in fact they are liberated mostly to return to the position that party nominees customarily occupy in American politics, with the Republican seen as stronger on national security and with the Democrat seen as more effective on economic issues. Ronald Reagan pulled the trick of being seen as both, which was one reason there were so many Reagan Democrats. Watch politics return to a natural equilibrium: The latest Zogby Interactive poll shows twice as many likely voters believing Mr. McCain is a better potential commander-in-chief, while Mr. Obama is viewed more as the competent manager, problem solver, and in sync with the average person. That may explain Mr. McCain’s midweek call for a suspension of the campaign; equilibrium is the enemy of insurgencies such as his.

This campaign has had several jolts — the latest ones put Mr. Obama ahead of Mr. McCain by nine points, according to the most recent Washington Post-ABC News Poll — but the nature of this campaign suggests that more jolts may follow.

One thing to remember as we go forward: Neither candidate was the favorite to win his party’s nomination. The nominees, watching the voters come back to their traditional musings, are practiced in the art of coming back themselves. More to come.

© 2008 The Pittsburgh Post-Gazette