Republican gubernatorial candidate Ed Gillespie, right, gestures during a debate with Democrat Ralph Northam on Oct. 9. (Steve Helber/AP)

A year out from the 2018 midterm elections, the two major parties are furiously cramming to learn everything they can about the nation's political climate in Virginia, home to Tuesday's hotly contested governor's race and several congressional battleground contests next year.

Governors' races are not a perfect match for gleaning the electoral mood in federal races a year from now, but Democrats and Republicans are monitoring key themes in Virginia — and they're ready to adapt, depending on the outcome.

Regardless of the victors Tuesday, some national strategies have already come into focus. Democrats will try to paint Republican incumbents as the incompetent, dysfunctional leaders of a Congress that did not fulfill President Trump's promise to focus on the "forgotten men and women" of the working class.

Republicans are placing their bet almost entirely on their ability to deliver a large tax cut, wagering that putting more money in people's pockets is the sort of deliverable good most voters will reward.

The contour of Senate seats up for election next year continues to make that body very likely to remain in Republican control, but initial expectations of significant Republican gains have evaporated.

At the same time, each side now admits that the House majority is very much up for grabs, more so than at any time since then-President Barack Obama's first midterm election in 2010, when Republicans took charge with a historic, 63-seat pickup.

"If we pass a middle-class tax cut, we will keep the House, period," said Corry Bliss, the executive director of the Congressional Leadership Fund, the super PAC affiliated with Speaker Paul D. Ryan (R-Wis.).

Left unsaid, of course, is what happens if Republicans choke on that plan. Democrats are trying to reassure their donors and activists, after years of explaining away their electoral failures with talk of gerrymandered districts, that the contours have shifted. Now, about 50 seats are in play — more than double the 24 needed to flip the majority.

"The map is not as bad as people think. There is a path to winning the majority," said Alixandria Lapp, founder of House Majority PAC, the Democratic super PAC.

That's where Virginia comes in handy, helping national party strategists see how messages are playing out in such a critical battleground state.

Democrats want to gauge the success of Republican Ed Gillespie's heavy focus in the final weeks of the race on illegal immigration and criminal gangs, particularly in the suburbs of Northern Virginia. Democrats have accused Gillespie of aping Trump's style after years of serving in the national Republican establishment as a champion of big-tent politics.

"Gillespie has run a campaign that has studiously avoided Donald Trump, but his television ads show that he is running a campaign like Donald Trump, and so how Virginians respond to that will also be somewhat indicative of the way they respond to the Trump political style," said Sen. Tim Kaine (D-Va.), who faces reelection next year.

But Republicans believe that the issue is more potent than Democrats realize, particularly in the key suburbs where several dozen House races will be fought next year. If Gillespie posts, for instance, a better-than-expected margin in the district of Rep. Barbara Comstock (R), that will reinforce such a position and lead to many more ads attacking "sanctuary cities" next summer and fall.

If Lt. Gov. Ralph Northam wins the district by a substantial margin, Democrats will feel much better. Comstock's is one of 23 Republican-held districts that favored Hillary Clinton in last year's presidential election. There are an additional 13 GOP-held seats in districts that previously voted for Obama but did not favor Clinton, and 14 more where either Obama or Clinton received at least 48 percent of the vote.

That is a better target list than in 2006, the last time Democrats flipped the majority to their side. Then, 17 Republicans held districts that had backed the previous Democratic presidential nominee.

Republicans have enjoyed watching the final two weeks of Northam's campaign play out amid much second-guessing by Democrats at the national level who think his campaign has not done enough to energize minority voters. That fear led one pro-immigration group to briefly run a controversial ad showing a Gillespie voter in a pickup truck trying to chase down minority children.

Republicans believe that liberal outrage over Trump's presidency could be a bonus to GOP candidates next year because the most loyal Democratic voters might demand that Democratic candidates take the most strident anti-Trump positions in primary contests, making them seem out of touch with the centrist districts Democrats need to win the majority.

If Northam loses, the liberal backlash will be swift. The question will be whether Democrats go down the same road as Republicans, whose voters have largely replaced ideological litmus tests with emotional demands; anger, not policy positions, is the big currency in GOP circles these days.

"The Democratic Party is being run by 20 people running for president in 2020," Bliss said. He made clear that his super PAC intends to wade into some Democratic primaries to try to tip the balance toward the more unelectable candidate for the general election.

But Rep. Gerald E. Connolly (D-Va.) said that candidates such as Northam, whose soft Southern drawl presents him as an emotional moderate, will benefit from the anti-Trump energy of the liberal base while appealing to independent voters looking for solutions.

Connolly predicted that Northam would win his Fairfax County-based district by similar margins as Clinton did last year, en route to a comfortable win of 5 percentage points statewide.

One big unknown will be money. Bliss has announced that the Congressional Leadership Fund is well on its way to spending more than $100 million to defend the House GOP majority, more than double what the PAC spent last year.

"Republicans see the wave coming, but they are trying to build a sea wall made out of money," Lapp said. Her group spent about $55 million promoting Democrats last year.

Kaine knows that sometimes these gubernatorial contests are signals of voter discontent. His 2005 victory in the governor's race presaged the 2006 midterm sweep by Democrats, just as Republican Bob McDonnell's blowout victory in 2009 showed that the GOP was headed for major victories in 2010.

A Gillespie victory might suggest that Kaine is in more trouble than most expect in his likely contest against Trump supporter Corey Stewart, but he is not waiting for Tuesday's results.

"I'm running like I'm endangered — I'm an endangered species," Kaine said. "I run all my races that way."

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