FOLSOM, Pa. — Patrick J. Toomey doesn’t have a problem with all Republicans who have been nominated for president. 

Just the one nominated this year. 

On Friday, the senator from Pennsylvania welcomed fellow GOP Sen. John McCain of Arizona to this small working-class town near Philadelphia. The two men spoke inside a local Veterans of Foreign Wars post, where Toomey made clear his affection for his party’s 2008 presidential nominee. 

“Sen. McCain doesn’t have a bigger fan in the United States Senate than me,” he said, in front of an audience of a few dozen veterans. “He’s a hero to me, as he is to everybody in this room.”  

Toomey doesn’t talk that way about Donald Trump, whose candidacy he has called “highly problematic.” It’s why he’s repeatedly said he’s not sure whom he’ll back even as he tries to win his own neck-and-neck re-election race against Democratic nominee Katie McGinty.

Toomey has stuck to his non-answer on the presidential race all summer and into early fall.

Politically speaking, party strategists say they have concluded that the animus that opposing Trump creates in the party’s base is a greater risk than whatever Trump-skeptical Republicans gain with moderate voters. 

That was evident even at Toomey’s rally Friday, where some Republican attendees expressed displeasure at the senator’s decision to not yet back Trump. 

“If Trump is the nominee, we should support him plain and simple,” said Ted Manna, a 54-year-old who attended the rally. 

Not backing Trump is tantamount to helping the Democrats, he said.

With just six weeks before Election Day, Toomey will soon need to decide if it’s the answer he wants stick with until Nov. 8.

If he continues to not give an answer, he risks antagonizing both base Republicans who want him to back Trump and moderate Democrats who loathe the GOP nominee but are open-minded about the senator. It might also give the media something to fixate in the race’s closing weeks instead of his message about jobs or national security. 

The Pennsylvania Republican declined again on Friday to say which candidate he’d vote for in November.

“I am still wrestling with what to do,” Toomey said after the rally. “There is no question I would never support Hillary Clinton under any circumstances, but like a lot of Pennsylvanians, I’m not happy with the choices we have. 

“We have a little time, and we’ll see,” he added.  

Toomey is just one of two Republican senators on the ballot this year who have not committed to supporting Trump, along with Illinois Sen. Mark S. Kirk. (Kirk takes his anti-Trump position a step further than Toomey, saying that he definitely won’t vote for the GOP standard-bearer.)

Most Republicans, including fellow vulnerable Sens. Kelly Ayotte, Rob Portman and Marco Rubio, have all backed Trump, though some have expressed reservations. 

That pressure to support the ticket was evident last week, when Texas Sen. Ted Cruz, a former presidential rival and avid critic of Trump’s, surprisingly announced that he would vote for him. 

Toomey might also have as much to lose as some expect if he backs Trump: McGinty and her Democratic allies already attack Toomey over Trump even though the senator hasn’t said he’ll support him.

“He’s disrespecting the media and his own constituents when he acts like saying he’ll never vote for Hillary Clinton means anything other than that he wants Trump to be president instead,” said Sean Coit, a McGinty campaign spokesman.  

But backing Trump comes with its own set of problems, especially for an incumbent whose re-election could depend in large part on performing well in the vote-rich, well-educated suburbs of Philadelphia. 

College-educated white voters have shown a greater suspicion of Trump than their blue-collar cohorts, and support for the GOP nominee could reduce the chance that they vote Republican down the ticket. 

“Right now, Pat Toomey is running for re-election in the Philadelphia media market,” said one Republican strategist watching the race. “That’s the whole ballgame.”