THERE'S no mystery

behind what looks like a surge for Pat Toomey.

Elections turn on windows opening at various times on various issues. Toomey's benefiting from an open window with a view of a sour economy.

And in the Senate race pitting Republican Toomey against Democrat Joe Sestak, at the moment little else matters: If that window stays open on the same view, you might want to get used to calling Toomey "Senator."

Sestak, naturally, disagrees.

He tells me that he sees no Toomey surge and says that Pennsylvanians realize that economic damage didn't just happen: "It happened on his watch [Toomey was in Congress from 1999 to 2005] and because of policies he supported."

Still, there's a wind at Toomey's back.

All polling shows dissatisfaction with incumbents on voters' top priorities - jobs and the economy. Toomey plays to this, asking, "Where is this recovery?"

And he localizes.

On a four-day bus tour across the state, he tells each county visited what the $787 billion economic stimulus cost residents and how much the unemployment rate rose in that county since the stimulus was signed in February 2009 - or, as Toomey puts it, "since Joe Sestak voted for the stimulus."

The calculation is simplistic - cost of stimulus per person times county population - but it's a clever way to make people mad.

In Monroe County, in the Poconos, for example, he says that the local cost is $436 million and that the unemployment rate is 10 percent, an 18 percent increase.

In Philadelphia, says Toomey's campaign, the cost is $4 billion and the unemployment rate is 11.9 percent, a 27.9 percent increase.

No question unemployment is worse. Statewide, the rate was 7.2 percent in February 2009; today it's 9.3 percent, according to U.S. Labor Department data.

Toomey this week said that 71,600 jobs have been lost in Pennsylvania since February 2009.

He blames President Obama, House Speaker Nancy Pelosi and, of course, Sestak.

And while blaming Sestak for a lack of recovery is as specious as Sestak's blaming Toomey's work on Wall Street or in Congress for creating the crisis, voters are more concerned with what's happening now than what happened then.

Same for Democratic arguments that without the stimulus things would be worse: Voters, rightly or wrongly, react to what is more than what-ifs.

Toomey touts lower taxes/less government, and Sestak supports government "investments," so recent polling shows Toomey ahead by eight or nine points.

And last week's Rasmussen Reports show two dark shadows for Sestak: Toomey holds a large lead among independents, and Democrats are far less enthusiastic about Sestak than Republicans are about Toomey.

This "enthusiasm gap" is dogging Democrats across the country and is a key reason why most analysts expect a strong Republican year.

Daily News pollster Terry Madonna, of the Franklin & Marshall College Poll, says that the "gap" is driven by the economy and a belief that "Democrats were elected to fix it and haven't." (A new Daily News/ F&M poll is due tomorrow.)

Larry Sabato, director of the University of Virginia Center for Politics, rated Toomey/Sestak a toss-up back in May. Now, he tells me, "Frankly, that's one of the ratings likely to be changing. Increasingly, it appears that the GOP is going to have a good year in Pennsylvania."

If so, it won't because of campaign sniping such as the claim that Sestak's a toady for Pelosi; too far left for a moderate state. Or that Toomey's a Wall Street hugger; too far right for any state not Wyoming.

Same with Toomey saying Monday at a Pennsylvania Press Club luncheon that he "never" supported privatizing Social Security, after saying in a 2004 candidate survey that he supports personal accounts for workers that they, not government, control; or Sestak playing the independent, backed by independent New York Mayor Bloomberg and former GOP Nebraska Sen. Chuck Hagel, after campaigning earlier this year as the only "real Democrat" running.

These sound bites are not central to the contest. The economy is overriding. And Toomey's overriding message is politically more potent than Sestak's - for as long as that window stays open and the view stays the same.

Send e-mail to baerj@phillynews.com.

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