BY AMBER PHILLIPS

 (AP Photo/Evan Vucci)

Up until recently, it has mostly been a theoretical assumption among some disgruntled Republicans in Congress that the GOP would, at some point, simply cut its losses with Donald Trump, and devote its cash and infrastructure to saving their congressional majorities.

On Thursday, that idea is becoming rapidly less theoretical. More than 70 Republicans signed an open letter released Thursday to Republican National Committee Chair Reince Priebus urging him to cut off cash from Trump. Earlier on on Thursday, Time magazine reported Priebus was considering it:

The chairman had a frank message for the nominee, according to two Republican officials briefed on the call. Priebus told Trump that internal GOP polling suggested he was on track to lose the election. And if Trump didn’t turn around his campaign over the coming weeks, the Republican National Committee would consider redirecting party resources and machinery to House and Senate races.

Trump denies the exchange ever took place. “Reince Priebus is a terrific guy,” Trump told TIME. “He never said that.” Priebus could not be reached for comment. But whatever the exact words spoken on the phone, there is no doubt that the possibility Republicans will all but abandon Trump now haunts his struggling campaign.

Miami Beach. (Photo by Joe Raedle/Getty Images)

That would indeed be a big problem for Trump, who has spent exactly $0 on TV ads, has just a fraction of rival Hillary Clinton's state-level field staff, and still has far less cash to spend on either than she does.

Money+votes = winning elections. Right now Trump doesn't have nearly enough of either without big help from Republican Party resources and infrastructure.

Despite Trump's struggling campaign — or maybe because of it — there are at least three clear reasons Priebus really could follow through on his threat and drop Trump to save his party in November: 1) money, 2) polls and 3) history.

A defiant Donald Trump at a rally in Florida on Wednesday. (AP Photo/Evan Vucci)

1) The Republican Party only has so many resources to go around.

Trump is raising money for Republicans -- some $80 million in July for both the party and his campaign. And the Republican National Committee has more than double the cash than Democrats' right now ($21 million to $9 million).

But  Trump also has a massive fundraising deficit. His campaign  had $1.3 million in the bank at the end of June. Clinton's: $42.5 million.

Which means resources are scarce, and we could see a world where Republicans want to hang onto theirs.

2) Senate Republicans don't seem positioned to outrun a Clinton tsunami

Depending on the day, depending on the poll, Senate Republicans are either hanging in there despite their nominee or getting dragged down with him. But overall, only two Senate Republicans of the 10 or so the party is fighting to defend appear to have enough of a head start to win if Trump were to lose their state by a significant margin. The only place we've seen Senate Republicans outperforming Trump is in Iowa, where longtime Sen. Chuck Grassley is outperforming his party's presidential nominee by 14 points, according to the most recent NBC/Wall Street Journal-Marist poll. And perhaps Ohio, where Sen. Rob Portman is consistently showing strong numbers, too, with that NBC poll showing him outperforming Trump by 10 points. But those are two seats out of a potential eight or 10 that could be in play. Republicans are already playing defense to keep their majority in the Senate. (Democrats essentially need to knock off four Republicans to take it back.)

And if Trump does really badly in November, even Republicans' historic majority in the House of Representatives could be in play. (Though that's much more of a long shot.)

It's not difficult to see a world in which Republican officials look at their flatlining balance sheet, look at Trump's near-weekly controversial statements and decide that their best investment is in ... themselves.

3) It has happened before

Republican vice presidential candidate Gov. Mike Pence chats with former Sen. Bob Dole at Republicans' convention in Cleveland in July. (AP Photo/Paul Sancya)

"If we fail to protect our majority in Congress, we could be handing President Hillary Clinton a blank check.”

When House Speaker Paul D. Ryan (R-Wis.) sent a fundraising email with that line last week, the political world freaked out over two words he used: "blank check."

That's the language Republicans used in 1996 when they decided to cut loose from sinking presidential nominee Bob Dole late in the election.

Then, as now, the party stood squarely behind its nominee. Until it didn't.

Donors aren't waiting, report Matea Gold and Anu Narayanswamy: "Some of the country’s wealthiest Republican donors are targeting Senate and House races around the country, hoping a financial firewall will protect the party’s congressional majorities on Nov. 8. Their investments — helping fuel a record haul by super PACs this year — reflect a fear prevalent throughout the party: that Trump’s contentious candidacy threatens an electoral rout up and down the ballot. ..."

Donald Trump might think he's winning ...

 

Everything's a-Okay. (Reuters/Eric Thayer) 

The polls -- Trump's best friend throughout this campaign -- haven't been going well for him lately. But he tried his best to explain why he thinks things are going pretty well.

Here's an interview with CNBC on Thursday. Click each link for a line-by-line annotation from The Fix's Philip Bump. But the point of sharing this interview is to relay that Trump is pretty optimistic about his chances. 

CNBC'S BECKY QUICK: If you look at the polls ...

TRUMP: I'm giving it straight. I don't know if it will work, because I'm a nonpolitical person and I'm proud of that, but I'm giving it straight. I've done a great job and now I'm doing a good job politically.  I mean, I came from this massive field of professionals, all governors and senators and people of vast talents and those people got knocked off one by one by one, and now I'm down to the final person and we're gonna see how that — you notice how the polls are closing up very rapidly,  which is fine.

Don't forget, she has spent hundreds of millions of dollars on advertising. You know what I've spent, Becky? Zero. 

QUICK: But you've lost some of the Republican women. The latest poll from the Wall Street Journal shows that it's 72 percent of the Republican women. Mitt Romney won 90 percent of that group and still didn't win the election. How do you ...

TRUMP: Alright. We'll see what happens. I mean, we'll see what happens. I have a whole group of people out there that people don't even know about. You know, I had a rally last night with 10,000 people. If Hillary had the rally, she would have had 200 people, if she was lucky. We'll see what happens. I don't know that that translates to votes. In theory, it should. But I don't know if it translates into votes.

… But one county suggests differently

(Philip Bump / The Washington Post)

In 2012, Mitt Romney tried hard to win Hamilton County, Ohio, which encompasses swingy Cincinnati, notes Bump

"Our operation has shown that we committed to running an aggressive, 88-county campaign," Romney's Ohio state chairman said in an email to the Columbus Dispatch that June.

So what's Donald Trump doing there? The Cincinnati Enquirer looked into it on Wednesday:

With the presidential election 90 days away, the Donald Trump campaign is scrambling to set up the basics of a campaign in Hamilton County, a key county in a swing state crucial to a Republican victory, a recent internal email obtained by The Enquirer shows.

The campaign has yet to find or appoint key local leaders or open a campaign office in the county and isn't yet sure which Hamilton County Republican party's central committee members are allied with the Republican presidential nominee. ... Even campaign materials, such as signs and stickers, aren't yet available.

OTHER TOP DEVELOPMENTS

  • Trump refuses to back away from his false claim that President Obama founded the Islamic State. At a rally in Miami Thursday, he repeated it again and again after initially drawing attention for making the claim Wednesday, writes the Associated Press's Josh Lederman. "No, I meant he’s the founder of ISIS. I do," Trump said. " ... He was the founder. The way he got out of Iraq — that was the founding of ISIS, OK?”
  • Thursday was Clinton's turn to give an economic speech. She spoke in a largely blue-collar town outside Detroit, the site of Trump's Monday economic speech, and tried to cast a contrast between her -- the supposed candidate for American workers -- and Trump -- whom she says will help the super rich --  according to The Post's John Wagner and Jim Tankersley: "Donald Trump wants America to work for him and his friends, at the expense of everyone else,” Clinton said. “He’s offered no credible plans to address what working families are up against today.”
  • Some liberals are not happy about Clinton's now-overt Republican outreach, writes The Post's David Weigel: "It amuses me how Democrats who once found these people appalling are now cheering them as useful weapons in their glorious battle against Trump," said Doug Henwood, a journalist who has written extensively about why progressives should not trust Clinton.
  • Clinton and her running mate, Tim Kaine, will release a new batch of tax returns in the coming days, reports The Post's Abby Philip. The move clearly puts pressure on Trump, who has said he will not release his tax returns because they are being audited, to do the same. 
  • Conservative Iowa congressman Steve King said at the Iowa State Fair on Thursday that he could work with Hillary Clinton if she were president.
  • ICYMI: The Post's David Fahrenthold and Robert O'Harrow Jr. combed through a 2007 deposition related to Trump suing a reporter for misstating his net worth. Over the course of two days of questioning, the reporter's lawyers caught Trump, under oath, misstating facts about his life 30 times. And here's the thing: Most of it was about random and very checkable stuff.

  • Trump on Christianity, to an audience of evangelical pastors in Orlando: "We're gonna bring it back."

THE VIEW FROM THE TRAIL

Donald Trump, who has been incorporating visual aids into some speeches, said Thursday that he had entered a "world of charts." EPA/CRISTOBAL HERRERA

YOUR DAILY TRAIL PIT STOP: Here's one of the selections from President Obama's final White House summer playlist, which landed today, late in the final summer of his presidency: "So Very Hard To Go"