Our newest round of NBC/Marist polls makes one thing abundantly clear: It’s increasingly likely that the uber-competitive Senate race in Iowa will determine control of the U.S. Senate. Why? Needing to pick up a net of six Senate seats, Republicans are now favored to win five of them (Montana, West Virginia, South Dakota, Arkansas, and Louisiana). Meanwhile, Democrats have the narrow edge in North Carolina (our NBC/Marist poll has Sen. Kay Hagan ahead by four points among likely voters), and Alaska is considered a jump ball, especially given the uncertain polling in that state. But if the new Senate math is that Republicans need to find seven Democrat seats -- with Greg Orman leading Pat Roberts in Kansas by 10 points in our new poll, and with no one certain with whom Orman will caucus -- then Republicans get to seven by winning Iowa and Alaska. (You can throw Colorado into this mix, too, but our belief is that if Democrats are going to win in Iowa, they’re probably going to win Colorado.) Bottom line: If you tell us who wins Iowa come Election Night, we’ll have a VERY GOOD idea of which party is going to win the Senate, even after the runoffs in December and January.

Ernst has the enthusiasm edge in neck-and-neck Iowa

So what does our NBC/Marist Iowa poll show? Republican Joni Ernst has a two-point advantage over Democrat Bruce Braley among likely voters, 46%-44%, which is within the survey’s margin of error. But as one of put it over the weekend, Ernst has the enthusiasm advantage. More than six in 10 Ernst supporters said they chose her because they actively support her candidacy, while 34% said their backing of Ernst was a protest against Braley. But those numbers were flipped for the Democratic candidate. About six in 10 Braley backers said their vote was mostly due to opposition to Ernst. And 62% of Ernst supporters were firm in their decision between the candidates, compared to 51% for Braley. “It’s all much more about Ernst than it is about Braley,” said Marist pollster Lee Miringoff. These numbers also are an indication of just how negative the race has become. Braley and the Dem Super PACs are almost entirely anti-Ernst now.

Reactive administration vs. proactive administration

As we wrote last week, the Ebola and Secret Service stories have become the latest examples where the political opposition and media can declare that government isn’t working. That was a question that White House Senior Adviser Dan Pfeiffer got on “Meet the Press” yesterday. Here was his answer: “Look, I do understand that people have had a growing skepticism of institutions for a long time, including government. But people should know that everyone in the situations you mentioned, where a problem arises, we deal with it. We deal with it quickly, we deal with it forcefully to make sure it doesn't happen.” He added, “Let's take one example that got a lot of attention over the summer, which is the surge at the southwestern border. That was a problem that came. We brought to bear every resource possible to do it. And this month, crossings at the borders are less than they were this time last year.” Pfeiffer is correct there. The problem for the administration is that it does a better job of being reactive, rather than proactive. It always appears as if the administration is a week or two behind where the public wants them to be. This may be an impossible standard for any crisis, but welcome to new media.

Axelrod: “It was a mistake” for Obama to say (in the way he did) that his policies are on the ballot

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Former Obama adviser David Axelrod was the latest to say that the president erred when he said his policies are on the ballot this fall. “If you read the speech, the context of the line was, the thing he's pushing forward, minimum wage, pay equity, infrastructure, and he said these are on the ballot,” Axelrod said. But he went on to say, “It was a mistake. But you know, fundamentally, the issue that he should be driving and the Democratic Party should be driving is forward looking, because the problem is how are middle class people going to make a living in this country, and what policies can we implement that can help? We ought to have that debate.” Yes, Obama stated the reality of this midterm season, especially in the GOP advertising in red states. But what that line did -- “I'm not on the ballot this fall. But make no mistake, these policies are on the ballot” -- was give Republican ad-makers further ammunition to nationalize these contests.

Another potential ‘16 Democratic candidate unwilling to criticize Hillary

NBC’s “Meet the Press” has now interviewed two potential Democratic challengers to Hillary Clinton -- first Sen. Bernie Sanders (I-VT), then former Sen. Jim Webb (D-VA) yesterday -- and both have been unwilling to criticize her, let alone distinguish themselves from her. Here’s Webb from yesterday:

CHUCK TODD: You don't want to talk about Hillary Clinton yet. Is that fair to say? You're not ready to talk about her?

JIM WEBB: I don't think it's for me to talk about Hillary Clinton. I enjoyed working with her when I was in the Senate. I don't know what she's going to do, if she runs, what she will run on. I'm just very concerned about these issues for the country.

But here’s the rub: If you’re REALLY going to challenge Hillary, you have to take her on -- to show to donors and supporters that any potential run is to actually win. It’s going to take guts to take on the Clintons. And if you’re going to do it, you’ve got to show it. It’s amazing to us how few Dems who want to run for president want to actually take her on. For now, all these potential anti-Hillary Dems look like they are running for the attention rather than the nomination.

RGA hits Democrats in two new TV ads

Turning back to the midterms, the Republican Governors Association is out with two new TV ads -- hitting Democratic Gov. John Hickenlooper in Colorado and Democratic Hawaii gubernatorial nominee David Ige. The first TV ad: “When [Hickenlooper] ignored our own Colorado sheriffs on gun control, or as mayor, allowed Denver to be a sanctuary city for illegal immigrants, we notice. But when he suggests giving a mass murderer clemency if he loses a political campaign, it’s shocking. Colorado has had enough of John Hickenlooper’s inaction and failed leadership. It’s time for a governor who will act.” The second TV ad: “With Neil Abercrombie’s support, David Ige co-sponsored the law that created the Hawaii health insurance exchange. And it’s been called the worst in the country. After hundreds of millions of dollars spent, a congressional review said it failed.”

First Read’s Race of the Day: NH-2: Kuster vs. Garcia

GOP state Rep. Marilinda Garcia is everything Republicans could want in a rising star– she’s young, telegenic and Hispanic. She’s also an unapologetic conservative (she suggested that the president has “many, many impeachable offenses,” for example) who may just be too far to the right in a district that’s supported Obama by double digits twice. She’s facing incumbent Democrat Rep. Ann McLane Kuster.

Countdown to Election Day: 29 days

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