Republican presidential candidate Donald Trump addresses the California Republican Party Convention on April 29, 2016 in Burlingame, California. Trump is preparing for the California Primary on June 7.  (Photo by Ramin Talaie/Getty Images)

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Trump adviser Paul Manafort met with Senate Republican chiefs of staff at an off-the-record lunch last week

Manafort gave GOP Senate hopefuls permission to keep their distance from Trump if necessary

CNN  — 

Donald Trump’s campaign is privately giving Senate Republicans in tough reelection races its blessing to avoid the presumptive nominee if he campaigns in their states, the latest effort by the unconventional candidate to build goodwill with a nervous GOP establishment.

Last week at an off-the-record lunch meeting in Washington, Trump adviser Paul Manafort told Senate Republican chiefs of staff that the Trump campaign wants to be helpful to GOP senators in tough races, according to three sources in the room. Manafort said if there are issues that put GOP senators in awkward positions, the Trump campaign would seek to avoid those touchy topics while campaigning in their states, attendees said.

And if Senate Republicans want to keep their distance from the campaign and avoid the candidate altogether, Manafort said, the campaign would not hold it against the vulnerable senators, the sources said.

The comments, while not entirely unheard of in the realm of presidential and Senate campaign politics, are the latest effort by the Trump campaign to build a relationship with congressional Republicans, who are battling to hold onto their narrow Senate majority and are still trying to determine how to handle their party’s presumptive nominee. Republicans realize they need Trump supporters, but are cognizant that his off-color rhetoric has turned off some key voting blocs in swing states. And if they avoid Trump, Senate Republicans want to ensure they are not the subject of a Twitter storm and a fusillade of insults from the provocative candidate.

Still, as polls show that Trump is on the upswing nationally, many Republicans are starting to get more comfortable with the billionaire real estate mogul as their party’s standard bearer.

“It’s very possible that he will be helpful to me,” said Sen. Rob Portman, who is facing a tough reelection in Ohio.

Asked if he would appear alongside Trump on the campaign trail, Portman told CNN, “If he wants to help, which he has indicated that he wants to – help House and Senate candidates – that’s good. He brought a lot of people into the primary.”

Even some Trump detractors are starting to show more openness. Pennsylvania Sen. Pat Toomey, who initially backed Sen. Marco Rubio for president then voted for Sen. Ted Cruz and later wrote an op-ed critical of Trump, said last week he wouldn’t rule out appearing at the same event as his party’s nominee.

“I’m definitely going to run my own campaign,” Toomey, who faces a grueling path to a second term, said on CBS Radio in Philadelphia last week. “We will run separate campaigns. Whether our paths cross, whether we are together at an event, I don’t know. I don’t rule that out. That would be a function of the logistics and what makes sense on a given moment in the campaign.”

Yet, several Republicans in difficult reelection races have tried to keep their distance from Trump, including Sen. Kelly Ayotte of New Hampshire who has said she would support the nominee but not offer an official endorsement.

The Trump campaign did not respond to an inquiry seeking comment.

In private, the discussion about Trump at the top of the ticket has become a source of increased chatter among Senate Republicans, including at a separate closed-door lunch last week where GOP pollster Frank Luntz laid out how the unpredictable candidate could affect the race for control of the Senate, according to senators who attended. (Luntz declined to comment.)

“He talked about the reality,” Indiana Sen. Dan Coats said of Luntz. “It’s a new ballgame, and old conventional rules don’t apply anymore.”

“Members are calculating – and I don’t think have reached a conclusion yet. Does Trump on the ticket help bring in new voters or hurt by being defeated in their state and having a down-ballot impact?” Coats said.

Republicans privately say that if Trump begins to struggle later in the campaign season, a growing number of GOP senators will likely abandon their front-runner.

But Texas Sen. John Cornyn, the No. 2 Senate Republican, said decisions on how to approach Trump will be made on a state-by-state basis.

“I think that’s probably a statement of the obvious: People are going to do what they view as maximizing their chances of success, and it’s going to vary perhaps by candidate and by state,” Cornyn said.

What’s made Republicans more comfortable with Trump are the spate of polls showing that Hillary Clinton is beatable in the fall. That was the message that Manafort delivered repeatedly in a round of meetings last week on Capitol Hill, including with the Senate GOP aides over lunch at a D.C. law firm, according to attendees. Manafort said that the campaign would seek input from lawmakers’ offices, especially as the candidate barnstorms across their states.

Asked if Republicans were more open to Trump now, Cornyn said, “I think there’s an acceptance to the fact that voters have made their choice. Every Republican I’ve talked to is not for Hillary Clinton, and that means they’ll support the nominee.”