The challenge for Democrats trying to take back the Senate is formidable. Ten Democratic incumbents are up in states carried by Donald Trump last year, five in states that Trump won by 19 points or more. This is a nightmare map for Senate Democrats. Realistically, there is only one way for Democrats to capture the three-seat net gain needed for a majority and that depends on Republican voters more than on Democrats or independents.

There are now signs that President Trump is succeeding in driving a wedge in the GOP between his base and the Republican Congress, blaming his own party for a lack of progress on Capitol Hill, something that could spell trouble for incumbents like Dean Heller in Nevada, Jeff Flake in Arizona, and possibly others. The danger is two-fold. Either the incumbent loses a primary to a less-electable Republican, or gets beaten in the general election because the party is so badly divided and Trump voters so disillusioned that usually reliable Republicans don’t go to the polls.

An Aug. 30-Sept. 7 survey in Arizona by Gerstein Bocian Agne Strategies of 600 likely voters in the 2018 general election and an additional 500 likely GOP primary voters lays out some pretty awful numbers for Flake. While the survey was taken by a Democratic polling firm for Senate Minority Leader Chuck Schumer’s leadership super PAC, I think these numbers are pretty much on target and underline the challenges the Republicans face this year.

First, let’s focus on Republican primary voters. Flake has a job approval rating of just 34 percent, with a disapproval rating of 59 percent. Twenty-five percent of GOP primary voters have a favorable personal opinion of Flake and 56 percent have an unfavorable view. His recent book, Conscience of a Conservative: A Rejection of Destructive Politics and a Return to Principle, was widely seen as a broadside attack on Trump and the recent direction of Republican politics. Though the title pays homage to Arizona Barry Goldwater’s 1960 book that helped make the senator a national conservative leader, it appears that the Republican base isn’t taking it that way.

A clue can be found in the favorability ratings of Senate Majority Leader Mitch McConnell. He has a 17 percent favorable rating, with unfavorables of 42 percent. His numbers show what happens when a Republican leader gets crosswise with Trump, who has an 80 percent job approval rating among self-identified Republicans. I think this is less about McConnell, per se, and more about Trump using him and House Speaker Paul Ryan as whipping boys instead of taking responsibility himself.

The wedge among Republicans is taking a toll on Flake in a primary matchup. He pulls just 31 percent against his announced GOP opponent Kelli Ward, who has the backing of 58 percent. In a 2016 GOP primary challenge to Arizona’s other senator, John McCain, Ward pulled 39 percent of the vote compared to McCain’s 51 percent.

The new poll showed that 44 percent of GOP primary voters had a favorable view of Ward and 19 percent unfavorable. That she overperforms her own favorability levels suggests that this is more about antipathy toward Flake than enthusiasm for Ward, an osteopath and former state senator. Two other Trump loyalists are also mulling the race: state Treasurer Jeff DeWit, who served as Trump’s state campaign chairman and chief operating officer for the national campaign, and Robert Graham, a former state GOP chairman.

Among the broader general-election pool of voters, 38 percent approve of Flake’s job performance and 50 percent disapprove; 23 percent have a favorable personal opinion of him while 48 percent have an unfavorable view. It appears that Flake’s attacks on Trump have caused many Republicans to turn against the incumbent, but Flake doesn’t pick up anything from voters who oppose the president. In a general election matchup, Democratic Rep. Kyrsten Sinema leads Flake by 7 points, 47 to 40 percent; her lead among independents is 13 points. Sinema has not formally declared her candidacy, but most analysts believe she will run.

Heller is also in the president’s doghouse, but Nevada is considerably more of a swing state than Arizona. He faces Danny Tarkanian, a Trump supporter who won the GOP nominations for secretary of state (2006), the 4th District (2012), and the 3rd District (2016). One key factor for both Flake and Heller is whether they face a single rival, with opposition unified behind one candidate, or several opponents, with the “anti” vote divided. They would obviously prefer the latter.

In a third insurgent-versus-establishment race, the GOP runoff in Alabama on September 26, a recent poll of 605 primary voters for McConnell’s super PAC showed former state Supreme Court Chief Justice Roy Moore leading appointed Sen. Luther Strange by 1 point, 41 to 40 percent. While Trump has endorsed Strange, he has not yet delivered on a promise to campaign for him, and his 83 percent favorable rating among GOP primary voters in Alabama may not be as potent as it appears.

Moore seems to have more appeal to Trump’s insurgent base while Strange’s backing is more upscale and establishment oriented. But Senate Leadership Fund ads attacking Moore would seem to be working, judging by a poll by Voter Consumer Research’s Jan van Lohuizen. Moore’s favorables have dropped from 59 to 54 percent over the last two weeks while his unfavorables have risen from 31 to 39 percent.

Theoretically, Senate Republicans should be on the offense next year, but intraparty divisions and primaries run the risk of costing the GOP a seat or two in a year when the political environment may be working against their chances of bumping off Democratic incumbents in Republican states. These divisions could end up costing the GOP an opportunity to build a larger and more durable majority than the scant 52-48 edge they have now.

This story was originally published on on September 15, 2017

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