Will Democrats have the money to win Congress? The Kochs are making me nervous. If you don't think money matters, you're wrong. We may have the advantage in enthusiasm, but Republicans will try to buy a ground game to match it.

Jesse Ferguson | Opinion contributor

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The Cook Political Report has said that “a wave is a comin'." And FiveThirtyEight argues that “the Democrats’ wave could turn into a flood.” In nine months, we’ll know whether Rep. Paul Ryan, R-Wis., is still speaker of the House and President Trump still has control of Congress.

In January 2010, President Obama had a positive approval rating (49% to 46.7%), and even he got shellacked in his first midterms. By contrast, Trump is under water by more than 11 points.

Democrats have a record number of compelling candidates, with veterans and women leading the charge. And according to Real Clear Politics, Democrats hold a 6-point lead in the average generic congressional ballot.

Surf’s up for the Democrats. Everything’s set for us to ride this wave to victory. Right?

I’m not so sure. I stay up almost every night worrying not just that the wave won’t be there, but that we won’t be able to ride it even if it is.

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When I started in politics, people obsessed that money was everything — the difference between winning and losing. It was the “mother’s milk” of politics. Now, the zeitgeist has flipped. Everyone either says money doesn’t matter or believes it will magically be there in the end. I’ve had countless Democratic strategists and candidates tell me not to worry.

Guess what? They’re wrong.

Money won’t determine the fundamentals of the cycle. It won’t transform an overwhelming loss into an overwhelming win. You can’t buy a wave.

But it can make a difference — a big one. In a cycle like this, I believe it’s the difference that could either end Republican control of the House on a close night, or limit our gains if the wind is really at our backs.

My night tremors got worse when the Koch network announced recently that it’s committing $400 million to preserve Republican control of Congress. Unlike most Democratic fundraising, the GOP is being rewarded by donors for passing an agenda that helps the donors. Trump's tax law gives the Kochs as much as a billion dollar tax break each year. Pay to play is contemptible but effective: that one donor is the equivalent of nearly 15 million Bernie-Sanders-style $27 contributions.

Beyond the Koch brothers, we already know that House Speaker Paul Ryan’s Super PACs raised $66 million in 2017. To put that in context, the entire budget for the Democratic Congressional Campaign Committee’s (DCCC) Independent Expenditure in the 2014 midterms was $67 million.

And then there’s the avalanche of cash we expect to see from the Todd Ricketts-funded 45Committee, the U.S. Chamber of Commerce and countless other dark money groups the GOP will engage.

With these massive resources, we can expect the Republicans to build a ground game and an air war like we’ve never seen. They’ll clog the airwaves and the Internet with advertising. They’ll be able to define their agenda early. Those ads are far more effective in midterm races and down-ballot elections than they are in a presidential election, where everyone knows the candidates. We might have the advantage in enthusiasm, but they’ll try to buy a ground game to match it.

The forgotten power of the purse in politics was proven when Democrat Ralph Northam defeated Republican Ed Gillespie for the Virginia governorship thanks, in part, to a $7 million financial advantage. And in the U.S. Senate race for Alabama, upset winner Doug Jones benefited from a $15 million advantage over Republican Roy Moore. “Simply put," Jones' pollster, Zac McCrary, wrote after the election, "the Jones campaign had the resources to pour gasoline on the fire that was already burning within the Democratic electorate.”

Can we afford the price of that gas in 2018?

Money matters even in years when there is a wave at your back. The 63-seat Republican wave of 2010 didn’t wash that far all by itself. It reached to Rock Hill, S.C., taking out veteran House Budget Committee Chairman John Spratt, thanks to a big ad campaign from a shadowy GOP group called the Commission on Hope, Growth and Opportunity.

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Four years later, when I ran the DCCC’s independent expenditures, I had to cut back on an ad buy in Arizona’s 2nd congressional district to try to keep another campaign afloat. Turns out, Republican Martha McSally won that Arizona seat by 167 votes. Money matters in close races.

We’re never going to match them dollar for dollar. Fortunately, in this climate, we don’t need to. We can tap into our supporters’ enthusiasm and majority disapproval of Trump. We can leverage the small-dollar donor base, give directly to campaigns, support local organizing efforts, and invest in national groups. We’re not powerless, but we’re taking on the powerful.

In the end, the wave might be big enough for us to change Congress. But I’d hate to wake up on Nov. 7 with 25 seats when we could have had 35 or, worse, with 23 seats when we needed 24.

Ultimately, as we head into the 2018 midterms, I’m confident that a blue wave is building. But I’m left wondering: Is our surfboard big enough?

Jesse Ferguson, a national Democratic strategist, has served as deputy national press secretary for Hillary Clinton’s 2016 presidential campaign, executive director of the Democratic Congressional Campaign Committee’s Independent Expenditure Program and communications director of the DCCC. Follow him on Twitter @JesseFFerguson