No one in American politics faces a steeper 2018 challenge than Rep. Steve Stivers, the Ohio Republican who leads his party's effort to retain its House majority in midterm elections. Even as the economy booms, polls show Democratic candidates with the upper hand. In special elections, Democratic partisans have shown greater enthusiasm for turning out to vote. An unusually large number of Stivers' fellow Republicans have chosen to retire. Trying to stave off a "blue wave," Stivers, who is chairman of the National Republican Congressional Committee, has assembled a highly regarded campaign team, worked to fatten the GOP's campaign treasury, and advised his candidates on effective messages and tactics. What the Eagle Scout and Iraq War veteran can't control is President Donald Trump, who has seized the loyalties of the Republican base and has made it harder for the party to reach beyond it. We sat down at the Ale House in Lancaster, Ohio, near Columbus to discuss Stivers' mission less than three months before Election Day. What follows is a condensed, edited transcript of our conversation. CNBC's John Harwood: Everyone seems to agree, you've got the toughest job in politics right now. Rep. Steve Stivers: It's a tough job. Harwood: Tell me about that. Stivers: But I feel good. Historically speaking, when the president and the House are of the same party, the House should lose about 30 seats. We have a 23-seat majority. That makes it tough. But the good news is we have our best candidates in our toughest races, 23 of them just ... in 2016 won an election in a district where Hillary Clinton also won.

We had more retirements than I would have liked, we had more special elections than I would have liked. But the special elections allow us to be battle tested. Harwood: You have an extremely strong economy now. Is the reason that Democrats are on offense and have a good chance, is that something that you guys have done? Is it something Trump has done? Stivers: We have known their side is excited since January, since the day after the inauguration last year when we saw a giant protest march in Washington. But we have a great economy. And I think that's why we're going to defy expectations. Harwood: The people who have turned away from the president and the Republican Party the most are more affluent, suburban, college-educated voters who are doing best in the economy. We've also seen that at crunch time in some of these races that you guys have been involved in, your candidates go not to tax cuts, not to the economy, but to immigration, ICE, MS-13, all that sort of stuff. Does that tell us that in this year, it's not the economy, stupid? Stivers: We've run ads on the economy in every single special election. But that doesn't mean that's what we will run on the whole time. The individual candidates still have to be held accountable for their positions and they can't run away from their positions or something that might motivate voters one way or the other. So, it was a piece of our message everywhere.

Rep. Steve Stivers with John Harwood Pat Anastaci | CNBC

Harwood: But not the dominant piece. Stivers: We are selling two things: We're selling peace and we're selling prosperity. We have security at home and abroad, safety at home and abroad, and we are selling prosperity. I think it is a dominant piece, it's one of two pieces of a pretty big puzzle. Harwood: We have very low unemployment, but we've also seen that wage gains are mostly being wiped out by inflation. There's some increased investment, but mostly a function of oil price, the rising price of oil. And all of the forecasters looking at the long term say we haven't changed the long-term outlook for the economy, we're still in that 2 percent range going forward. Does that mean, or does that tell you that you guys didn't pass the right tax cut? Stivers: I don't think that tax cuts, themselves, can grow the economy for 20 or 30 years, but they can set up a situation where there's an incentive. And what we have seen is really robust economic growth, and that's because there is investment. Harwood: But nobody expects it to last very long. Stivers: I believe it'll last longer than people think — but we will — you know, we'll see that quarter to quarter. I think the new problem we have is we don't have enough labor supply and we're already seeing that, and I think that is going to lead to wage increase over time here. Harwood: Let's talk about Nancy Pelosi for a second. Because you guys want to talk about her. How powerful a weapon can she be for you in an election year that is completely dominated by Donald Trump? Stivers: Part of our job is to make this election year a choice. And ironically, Nancy Pelosi, I think in every survey I've seen, is actually less popular than President Trump. Everywhere. Harwood: Also less important. Stivers: Fair point. But we need to make this election a choice. We will make it a choice on health care, we will make it a choice on safety and security, we will make it a choice on economic policies, and I think those three things matter to people. And if they don't, you know, we're going to have a long night. Harwood: Do you think that focusing hard on Pelosi poses any risk for you in a year when women, especially college-educated women, seem to be powering the Democratic campaign? Stivers: I think people know what they think about Nancy Pelosi, and it's not personal. It's what they think about her policies. Harwood: What do you think about her personally? Stivers: She's a lovely lady, personally. Harwood: Do you consider her a friend? Stivers: She's a nice lady. I don't know her really well, but she's a nice lady. And she and her husband, Paul, are nice people. I think they're good human beings, but the policies that she stands for are outside the mainstream of America and I think that's the point. And, you know, as far as women go, we've recruited 120 women to run for Congress as Republicans. Harwood: Democrats say if they win the House back, that most of those new Democratic seats are going to be held by women. Stivers: That's possible. They've got a lot of women recruits, too. So, you know, the good news is there will be more women in Congress in January of next year. Harwood: What do you think about the Mueller investigation? Do you think it should go forward? And do you have any concern about a fall surprise that would be damaging to your candidates? Stivers: Well, like most Americans, I'd like to see the Mueller investigation wrap up at some point soon. But I also want it to be fact-based, and I want them to wrap up at the right time.

Well, like most Americans, I'd like to see the Mueller investigation wrap up at some point soon. But I also want it to be fact-based, and I want them to wrap up at the right time. Rep. Steve Stivers Republican of Ohio

Harwood: You don't want to cut it short? Stivers: I'd rather not have them do something in the middle of an election that could impact an election. Regardless of which side you were on in 2016, I think we all would acknowledge the Federal Bureau of Investigation and the Justice Department played an outsized role in the presidential campaign, and I don't think that's right or fair. Harwood: You won a Bronze Star for your service in Iraq. Stivers: I did. Harwood: How do you feel about two things: one, when President Trump talks about the Iraq War as a disaster that should never have happened? And two, the possibility that his campaign was engaged in conversations with Russia to impact our election? Stivers: I don't believe that Vladimir Putin has America's best interests at heart. I still serve as a brigadier general in the Ohio National Guard, and I believe they are one of our global adversaries. And I don't believe the Iraq War was a complete disaster. I think we made mistakes. A lot of great people gave their lives for some really important things that happened Harwood: How do you feel when the current commander in chief runs down that effort? Stivers: Everybody's entitled to their opinion. You know, one of the reasons I have served in the military is I believe in the First Amendment to the Constitution's every individual's right to say what they want. It doesn't change what I believe, though. Harwood: You were also an Eagle Scout. Stivers: I am an Eagle Scout, yes. Harwood: How do you feel when you see this seemingly endless run of allegations: porn stars, playboy models, hush money? Stivers: Well, it's not the way I live my life. Harwood: Is it embarrassing? Does it bother you? Stivers: Some people live rock star lifestyles. I like hanging out here in Ohio, in Lancaster, at the Ale House, with people here than folks in Los Angeles or some places that are maybe more elite. I think all that stuff is embarrassing whether it's a Republican or a Democrat. It's unfortunate. But I think there's great things going on, too. Joyce Beatty, who's a Democrat from Columbus, and I came together and created the Civility and Respect Caucus.

I think we need more people to lead by example, and that's what I've tried to do, and that's what I'll try to continue to do. Rep. Steve Stivers Republican of Ohio