Six weeks before the election, campaign cash is flooding into these tight House races

With just six weeks left to the crucial November election, a handful of battleground races for seats in the U.S. House of Representatives have captured an outsized share of campaign cash in the 2018 midterm cycle.

Much of that cash is coming from political action committees, or PACs, and other so-called "soft money" groups that can accept unlimited contributions, as long as they don't coordinate their spending with individual candidates.

The money is funding a blizzard of television and digital ad campaigns aimed at flipping control of Congress from Republican to Democratic control.

Democrats face long odds in the Senate, but political pundits give them much better chance of picking up a net gain of 23 seats in the House, which would give them a slim majority in the lower chamber.

Over the last several election cycles, "soft money" has played an increasingly important role in overall campaign finance.

As of the end of September, total outside spending totaled roughly $460 million, about evenly split in favor or Republicans and Democrats. The case has also supercharged a handful of tight races around the country.

Brendan McDermid | Reuters

Democratic congressional candidate Conor Lamb is greeted by supporters during his election night rally in Pennsylvania's 18th U.S. Congressional district special election against Republican candidate and State Rep. Rick Saccone, in Canonsburg.

Pennsylvania 17th

It's not surprising that Pennsylvania's 17th is seeing a flood of cash, thanks to a realignment of a congressional districts that landed two incumbents in a race for the same seat.

This recently redrawn suburban Pittsburgh district pits Democrat Rep. Conor Lamb – who won his seat in another district in a special election last spring. Lamb is running against another incumbent, Republican Keith Rothfus, who currently represents the old Pennsylvania 12th district, which overlaps heavily with the new 17th. The maps were redrawn after the Pennsylvania Supreme Court ruled in January that the old districts were unconstitutionally gerrymandered in Republicans' favor.

The race in the new 17th has touched off a campaign finance slugfest between the major party finance arms, the Democratic Campaign Congressional Committee (DCCC) and the National Republican Campaign Committee (NRCC).

Lamb became a familiar name in Pennsylvania after a narrow win in a widely watched in March special election for Pennsylvania's 18th Congressional District. That seat had been held by a Republican for over a decade, and President Donald Trump won the district by 20 points. Political pundits have given Democrats a slight edge.

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Republican Greg Gianforte speaks to supporters after being declared the winner at a election night party for Montana's special House election against Democrat Rob Quist at the Hilton Garden Inn on May 25, 2017 in Bozeman, Montana.

Montana At Large

Montana has also seen a torrent of outside spending for its statewide at-large Congressional district, following a special election in 2017 to fill a seat left vacant after Republican Ryan Zinke resigned to become Secretary of the Interior in the Trump administration.

Rep. Greg Gianfortenarrowly won that race in a costly and closely-watched campaign, which included Gianforte's pleading guilty to charges of physically assaulting a reporter the night before the election.

It's been two decades since Montana sent a Democrat the House, and state Rep. Kathleen Williams is hoping to break the GOP winning streak. After prevailing in a six-way Democratic primary in June, Williams is hoping to capitalize on frustration with the GOP-controlled Congress.

Montana voters have elected both a Democratic Senator and governor, but the state voted for President Donald Trump by nearly 21 points in 2016.

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Harley Rouda, Democrat running for California's 48th Congressional district seat in Congress, listens to speakers during his campaign rally in Laguna Beach, Calif., on May 20, 2018. 

California 48th

This coastal southern California district, one of the tightest races in the country, pits incumbent Republican Dana Rohrabacher against Democrat Harley Rouda, a lawyer and real estate businessman.

According to a recent New York Times/Siena College poll, the race is a dead heat, with both Rouda and Rohrabacher drawing 45 percent of the vote.

An affluent Southern California district, the 48th District has been a traditional Republican strong hold. The GOP holds a 10-point advantage in voter registrations, but Hillary Clinton won the district by two points.

Rouda was endorsed by both progressive groups and the mainstream DCCC in a contested primary. Rohrabacher voted to repeal and replace the Affordable Care Act, but voted against the tax reform bill.

Thomas McKinless | CQ-Roll Call | Getty Images

Mike Levin

California 49th

The bulk of outside spending in the race for this open seat is flowing to the Democratic candidate, Mike Levin, a lawyer who has been active in environmental causes. He faces Republican Diane Harkey, a former state lawmaker.

Since 2000, this Orange County district had been held by Republican Darrell Issa, who announced his retirement in January.

So far, Levin has also outraised Harkey in direct campaign contributions with about $2.6 million, more than three times as much as his opponent.

The heavy cash advantage seems to be paying off for Levin. He leads with a 51 percent to 41 percent advantage in the latest New York Times Siena college poll.

Patrick T. Fallon | Bloomberg | Getty Images

Young Kim, Republican U.S. Representative candidate from California, waves during a Fourth of July parade in Hacienda Heights, California, on Wednesday, July 4, 2018. 

California 39th

Both parties see an opportunity in this seat vacated by the retirement of incumbent Republican Ed Royce. The district sprawls across parts of Los Angeles, Orange and San Bernardino counties.

Though Royce has held the seat since 2013, Clinton carried the district by nearly 9 percentage points in 2016. The campaign to fill Royce's seat pits Democrat Gil Cisneros against Young Kim, a Republican former state Assembly member. Cisneros, a philanthropist and Navy veteran, won a $266 million jackpot in the California lottery with his wife in 2010.

Kim, a former state legislator, has been endorsed by Royce. That endorsement seems to be paying off: Kim is enjoying a 10 point lead, according to a recent Monmouth University poll.

Cisneros has raised roughly $5.5 million to Kim's $1.2 million in direct contributions as of the latest campaign finance report.

Harry E. Walker | MCT | Getty Images

Jason Crow 

Colorado 6th

Democrats are spending big to unseat incumbent Republican Mike Coffman in this suburban district that voted for Clinton by nearly 10 points in 2016.

Coffman faces Democratic challenger Jason Crow, a lawyer and former Army Ranger, who is appealing to voters as a check on President Trump. That campaign strategy has prompted Coffman to distance himself from the White House.

So far, outside spending is about evenly matched: Both sides have raised about $2.3 million each in direct contributions, based on the latest campaign finance filings.

Recent polling shows Crow with a substantial advantage, with 51 percent of voters to 40 percent for Coffman, according to a New York Times/Siena College poll.

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