By Michelle Hackman

The most competitive contests for the U.S. Senate this year are spending more money than ever, with the Pennsylvania race between GOP incumbent Sen. Pat Toomey and his challenger, Democrat Katie McGinty, leading the pack as the most expensive in history.

That race, one of the closest of the year, has already surpassed $162 million in spending. Mr. Toomey, a first-term senator, is one of nine Republicans running in states that President Barack Obama won either in 2008 or 2012. But his race, nonpartisan analysts say, was considered one of just a handful of the purest tossup on the map -- hence the heavy spending there.

Already this year, two races have surpassed the record set in 2014 in the North Carolina contest between then-Sen. Kay Hagan and Thom Tillis, who unseated her. In that race, candidate and outside spending topped $114 million -- $10 million more than the next most expensive Senate race that year. In 2012, the most expensive race of the cycle was in Massachusetts, at a price tag of nearly $90 million.

This year, the influx of spending in Senate races reflected the degree to which some top Republican outside groups, including outfits run by GOP strategist Karl Rove and the Koch brothers, opted not to spend on the candidacy of the party's presidential nominee, Donald Trump, and instead direct their considerable resources to Senate contests.

Senate money also moved around the map in 2016, reflecting the changing calculations by parties and outside groups as individual races changed -- some that looked highly competitive early in the cycle, like Ohio and Florida, ended up being less so, while some such as Indiana and Missouri arecloser than expected.

Pennsylvania was one of the most consistently competitive. Of that state's Senate race total, which encompasses both the primary and general election campaign, $115 million came from outside groups, including party committees and super PACs, according to the Center for Responsive Politics.

"When you see a truly competitive environment, you see the spending just balloon," said Josh Stewart, a spokesman for the Sunlight Foundation, which tracks money in politics. "Outside groups beget more outside groups, and almost every outside player is in Pennsylvania."

A unique set of circumstances put the cost of Pennsylvania's Senate seat above the rest. It opened with a competitive Democratic primary contest, between Ms. McGinty and former Rep. Joe Sestak. Several outside groups -- including the Senate Democrats' campaign arm and Emily's List, an organization that promotes female candidates -- intervened on Ms. McGinty's behalf, driving up the race's price tag early.

The state is also home to some of the nation's most expensive media markets in Philadelphia and Pittsburgh. In addition to television and digital advertisements, some super PACs, including the league of Conservation Voters Action Fund, invested to set up ground operations, an expensive proposition in the sprawling state.

Republican spending was bolstered mainly by the Senate Leadership Fund, a super PAC aligned with Senate Minority Leader Mitch McConnell (R., Ky.), which invested over $15 million there. The network of groups backed by billionaire industrialists Charles and David Koch also made re-electing Mr. Toomey a priority, pouring in $10 million between its super PAC, Freedom Partners Action Fund, and a nonprofit group, Americans for Prosperity, which isn't required to disclose its donors.

But as in other states, a smaller band of conservative spenders were outflanked bya broad coalition of liberal outside groups, including labor, environmental and women's organizations, whose combined firepower overcame Republicans' big-dollar donor advantage. In all, liberal outside groups spent $62 million backing Ms. McGinty, while conservative groups spent $52 million for Mr. Toomey.

Two other Senate contests also topped $100 million in spending: New Hampshire, at $120 million, and Nevada, at $110 million. Both are also considered tossups.

GOP groups paid particular attention to Nevada, where Senate Minority Leader Harry Reid's retirement opened the best opportunity to pick up a Democratic seat. Outside groups spent over four times as much as the candidates to influence the outcome of the contest. Chief among them were the Koch brothers, who used the race as an opportunity to target Mr. Reid, a perennial foe. They invested $9 million in total, including a robust ground effort.

Florida and Ohio, the next two most expensive races, both saw infusions of outside spending early on, when analysts believed they would shake out to be the most competitive of the map. That early cash influx, coupled with Florida Sen. Marco Rubio's late decision to seek a second term in June, allowed Republicans to consolidate leads in both places -- considerably slowing the money pouring in to defend the incumbents or bolster their challengers.

By contrast, Missouri, North Carolina and Indiana were all home to contests that grew unexpectedly competitive late in the election season, setting off a frenzied last-minute push to air ads in those races. All three surpassed $60 million in spending, with North Carolina reaching $76 million.

Of the 10 most expensive races this year, only Wisconsin and Illinois, both at the bottom of the list, saw more spending by the candidates than by outside groups. In both races, Democrats were heavily favored to win, though the Wisconsin race has tightened in the closing weeks. In Illinois, the candidates spent $28 million, compared with only $4 million contributed by outside groups.

Overall, candidates and outside groups spent a total of $1.8 billion on Senate and House contests, according to data provided by the Campaign Finance Institute. That actually represents a slight decline from the last campaign held concurrently with a presidential contest in 2012, when candidates and outside groups spent more than $1.9 billion. The decline is in line with a larger reduction in election spending this cycle.

Among House races, the most expensive contest unfolded in the district encompassing Palm Beach, Fla. -- the seat that Rep. Patrick Murphy vacated to run for the Senate. Much of the $23 million spent on that contest alone came from the candidates themselves; the Democrat running, Randy Perkins, is a millionaire businessman who self-funded his candidacy.

A Las Vegas-area seat being vacated by GOP Rep. Joe Heck has been the target of the next most cash -- with over $21 million spent there to try to flip the seat into the Democrats' column.

Another seat, in Minnesota's working-class iron range, also involved over $20 million in spending -- with both the primary Democratic and Republican super PACs working to elect House members making it their top target. Rep. Rick Nolan, whose district is favorable territory for Republican nominee Donald Trump, is perhaps the most vulnerable incumbent Democrat in the country, and the GOP has spent millions to defeat him.

(END) Dow Jones Newswires

November 07, 2016 15:10 ET (20:10 GMT)

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