Wisconsin Gov. Scott Walker, accompanied by President Trump, center, and Ivanka Trump, left, speaks at a workforce development roundtable at Waukesha County Technical College in Pewaukee, Wis., in June. Just 41 percent of Wisconsin voters approved of Trump’s job performance in late June, while 51 percent disapproved, according to a poll by Marquette Law School. (Andrew Harnik/AP)

Senate Republicans began this year thinking that they had leverage over some Democrats, particularly the 10 up for reelection next year in states that President Trump won in the fall.

Those Democrats, some GOP strategists believed, would want to work with the president to appeal to enough Trump voters to win their states in November 2018.

That didn’t happen. Instead, Trump’s standing has slipped in many of these states. The president has faced legislative gridlock and a deepening investigation of his campaign’s connections to Russia. His focus, in public appearances and on social media, has regularly drifted away from the policy agenda on Capitol Hill.

That’s left Senate Democrats feeling stronger than they expected to be eight months after their highly disappointing showing in 2016, which left them in the minority and heading into 2018 defending 25 seats compared with Republicans’ eight.

If Trump had spent his first six months increasing or even maintaining his popularity in these states, he might have struck enough political fear in these 2018 Democrats to compel them to support some of his initiatives.

That’s looking more and more like the sort of negotiation that will happen only if Democrats can command a good deal in return.

The dynamic is sure to test Senate Majority Leader Mitch McConnell (R-Ky.) in the months ahead, particularly if Republicans fail to muster the votes solely from their side of the aisle to repeal chunks of the Affordable Care Act. McConnell has warned that such an outcome will force him to work with Democrats to shore up imploding insurance markets.

“No action is not an alternative,” McConnell said Thursday while in Kentucky.

Beyond the health-care fight, McConnell has also made clear that there are many other agenda items that will require the traditional 60-vote threshold to choke off filibusters, meaning he needs at least eight Democrats to move legislation such as annual government funding bills and an increase in the government’s borrowing authority.

But the bargaining table is different now.

Take Sen. Tammy Baldwin (D-Wis.), whose state delivered a critical victory for Trump, the first by a GOP presidential nominee since 1984.

A staunch liberal, Baldwin began the year expecting her 2018 reelection bid to be a 50-50 prospect. Her state had voted Republican three straight times for governor and in two of the past three Senate races.

Trump has used the presidential bully pulpit to focus on the Badger State, making three trips there since November. But his visits have done little to boost his standing.

Just 41 percent of Wisconsin voters approved of Trump’s job performance in late June, while 51 percent disapproved, according to a poll by Marquette Law School.

On basic popularity, Trump is easily the most disliked politician among Wisconsin voters, with 54 percent holding an unfavorable view of him and 40 percent a favorable one.

Baldwin’s image is not great, but it is far better in Wisconsin’s eyes than Trump: 38 percent have a favorable view and 38 percent unfavorable.

It’s the same in Michigan and Pennsylvania, both states Trump narrowly won. In Michigan, just 35 percent of voters approved of his job performance in a late May poll conducted by EPIC-MRA, with 61 percent disapproving. In Pennsylvania, 37 percent supported his job performance while 49 percent did not, according to a May poll by Franklin & Marshall College.

The good news for Trump is that his image in Pennsylvania improved a little from earlier in the year. The bad news is that his image in Michigan got a bit worse. The really bad news is that Trump’s image is battered enough that neither Sens. Robert P. Casey Jr. (D-Pa.) nor Debbie Stabenow (D-Mich.) are feeling much pressure to work with Trump in the run-up to their 2018 reelection bids, unless it’s on their terms on a critical issue for their state.

“For senators who hail from states where he is completely underwater, there is no political reason to work with him unless it’s on an issue where they have something to gain,” said Matthew Miller, a former aide to the Democratic Senatorial Campaign Committee.

It’s not just Trump who is unpopular; so is his party’s health-care proposal.

Late last month, two liberal super PACs, Priorities USA Action and Senate Majority PAC, released a poll of the 10 states Trump won where Democrats face reelection next year. It showed that 60 percent of voters in those key battlegrounds want the Senate to start over on a health-care plan, while only 25 percent support its passage.

The super PACs did not release Trump-specific data, but several sources familiar with the poll said that the Democratic groups also privately tested the president’s standing with voters in those 10 states. Only in the most conservative of those states, such as West Virginia and North Dakota, did Trump have a net positive approval rating, but even there his approval was only a handful of points higher than his disapproval.

Trump won West Virginia and North Dakota by 42 and 36 points, respectively. Under normal political circumstances, Sens. Joe Manchin III (D-W.Va.) and Heidi Heitkamp (D-N.D.) should be trying at every turn to work with Trump — much as Southern Democrats supported Ronald Reagan’s early agenda when the Republican icon swept that region in 1980.

After initial meetings with Trump during the transition, during which their names were floated as potential Cabinet members, Manchin and Heitkamp have kept a respectful distance from the president on most issues. Unless Trump can regain his strong popularity in these conservative states, the two are unlikely to feel the pressure to support the president, particularly when he’s pushing very conservative agenda items.

“You have to demonstrate that you respect the office and are willing to work with him, but hold firm to your principles on core issues,” Miller said, describing Manchin and Heitkamp’s approach.

During the spring negotiations over 2017 government funding, Democrats held firm against most of Trump’s priorities, including money for a Mexican border wall. Republicans got very few conservative wins.

If Trump isn’t careful, this dynamic might start repeating itself for the foreseeable future.

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