Senior Republicans are sounding the alarm about Rep. Lou Barletta's, R-Pa., struggling Senate campaign in Pennsylvania, fretting that his lackadaisical, disorganized effort will hand a third term to incumbent Sen. Bob Casey, D-Pa.

President Trump rallied support for Barletta in a string of Wednesday afternoon tweets. But the congressman is taking fire from Republicans at home and in Washington who worried that he is relying too much on the president to boost his flagging Senate bid. Barletta has been a disappointing fundraiser and been too slow to ramp up a capable statewide campaign operation, his critics charge.

"The sense is, nobody knows what the fuck he’s doing," a Republican strategist with Pennsylvania ties said, requesting anonymity in order to speak candidly. "He's not really working it hard. It's a sad thing, because people like Lou."

"Casey should be vulnerable," this Republican added. "But Lou is just like a ghost."

Red flags about Barletta were raised anew after he won the party's Senate nomination on Tuesday with 63 percent of the vote despite being Trump's handpicked candidate and enjoying the support of Pennsylvania's GOP machine. The fourth-term congressman defeated little-known and underfunded state legislator Jim Christiana. Barletta's camp dismisses the criticism, pointing to Casey receiving only 62,000 more votes than those in the GOP primary combined despite registered Democrats outnumbering Republicans by more than 800,000. They also insist that Barletta isn't running a sluggish Senate bid.

“Lou Barletta is working his ass off to beat Bob Casey in November," said Jon Anzur, Barletta's deputy campaign manager, in a statement. "Last quarter, Lou raised $1.3 million, the most he’s ever raised and among the most of any Senate challenger in the country. This week, Lou secured the Republican nomination for the Senate with 63 percent of the vote in his first statewide race. And nowhere in America is the president is more engaged in helping the Republican candidate win than he is with helping Lou Barletta in Pennsylvania.”

The Senate hopeful's defenders maintain that before the primary he did interviews in every media market in the state and held rallies across the commonwealth.

Yet Barletta has been hampered by lackluster fundraising, raising just over $500,000 in 2017 before boosting that to $1.2 million during the first three months of 2018. The first quarter figure placed him fourth among the Republicans running in competitive Senate contests, but was not enough to calm Republican nerves. Casey has $10 million and counting to burn in an expensive race that probably requires a minimum $20 million to be competitive, and Republicans worry Barletta won't keep pace as other Senate races remain at the forefront.

"There are six or seven other races that are much more attractive from a fundraising point of view than slogging it out in a state like Pennsylvania," former Sen. Rick Santorum, a Barletta supporter, told the Washington Examiner. "People tend to like to win states like Montana or North Dakota, which are a lot less expensive than Pennsylvania. I get it. He's going to have a hard time — he's got to continue to show that his race is a viable race."

"I think this race will be one of those races if they don't fund, they're going to kick themselves in November for not having funding," Santorum added, who still believes the race is "winnable" for Barletta.

Barletta's campaign maintains that they are outpacing their first quarter numbers in the second quarter. According to the pre-primary FEC report released in late April, the campaign raised nearly $200,000 in the first three and a half weeks since the end of the first quarter and had $1.3 million in the bank.

Nevertheless, the fundraising issue has remained a constant source of criticism for Barletta's campaign. According to a second Pennsylvania-based GOP operative, Barletta has had trouble connecting with donors, even as the race moves closer to the final six months before Election Day. The operative described a fundraising event Barletta held alongside Sen. Pat Toomey, R-Pa., in Philadelphia last week where he had issues keeping the attention of the 20-deep donor crowd at the lunch.

"Of the 20 people, 15 of them fell asleep," the operative said of the event, which was held at the Union League in Philadelphia and raised $48,000 for Barletta's campaign. "He's just not a good speaker."

The operative also said that Barletta's campaign has been disorganized and that selling the right story in the right areas of the state has been a constant issue. At one point, according to the operative, Barletta suggested having Trump come to the Philadelphia area for a fundraiser in April or May, but the idea got scrapped immediately due to the president's unpopularity in the region.

"You don't bring Trump down here. He's poison," the operative said. "The problem is the campaign seems disorganized, disjointed. I don't think they have a game plan ... You've got to use the message where the message sells. It's alright to talk about not letting any illegal immigrants in, but you don't use that in the city of Philadelphia, or Reading ... or Lancaster."

Despite the criticism, Barletta still has one big thing going for him: Trump's backing. The president tweeted three times on Wednesday in support of the former Hazleton mayor, including two aimed at Casey, who he derided as a "do-nothing senator" and "Bobby Jr.," referring to his father, Bob Casey, the late former governor of the state.

The campaign also argues that Trump is more engaged in the race than anywhere else in the country, with the president having recorded a robocall ahead of primary day, along with the series of tweets from Trump and Vice President Mike Pence. The campaign also said they are having active conversations with the White House regarding a campaign stop to the state by one of the two White House heavy hitters.

While Trump appreciates Barletta's steadfast support throughout the 2016 campaign, Republicans believe the president needs to be increasingly engaged in the state for both Barletta's sake and for his own. The president won Pennsylvania by just over 44,000 out of more than 6 million votes cast.

"I assume [Trump's] running again. He says he is. Well, this is a nice little trial run of your team and of your ability to attract votes in one of those key states he has to win in the fall," Santorum said. "This doesn't just help Lou. This helps the president "