Philadelphia's hottest protest is Tuesdays with Toomey — still protesting Trumpism and a certain junior senator from Pennsylvania long after the naysayers predicted they would have packed up their angry signs and gone home.

This place has everything — a drag queen billionaire "Rebekah Mercer" sweating in heels and a thick fur coat,  and a green "Swamp Queen" lobbyist who stuffed Monopoly dollars in her canvas money bag as she channel answers to questions from the molded Big Giant Head of a faux Sen. Pat  Toomey.

And on Tuesday it even had something else: Birthday cake.

It's been a year and a half (that's 78 Tuesdays, if you still believe in science, or at least math) since some dazed and disgruntled survivors of the 2016 election — keeping in touch on pro-Hillary Clinton websites like Pantsuit Nation — decided they had to find a positive outlet for their political grief.  The idea they came up with — bringing their weekly concerns to the office of a Republican senator who'd been elected with what proved to be an empty promise to stand up, on occasion, to President Trump — has kept several dozen of them together through rain and snow and now this wicked hot May afternoon.

The only thing that's been missing, largely, has been … the flesh-and-blood Pat Toomey. (His staff, which met more actively with the protesters in the early weeks, now sends someone down to listen and gather any cards and messages at the end of the protests at the 2nd and Chestnut office, according to the senator's spokesman Steve Kelly, adding that the senator met with selected protesters a half-dozen times last year.) About six bored-looking members of the police Civil Affairs Unit or unformed cops paid half-attention to this remarkably non-threatening group — sprinkled liberally with retirees and disability-rights activists, about two dozen in all.

"We'll be here every single week until he" — Toomey, that is — "speaks with us or until he leaves office," Vashti Bandy, the green-skinned, blonde fright-wigged "Swamp Queen," told me, before adding quickly, "probably when he leaves office." Which — assuming he doesn't run for re-election and win — would be January 2023, which, measured in Trump Years, is eternity plus one.

I spent Primary Day at the Tuesdays with Toomey birthday-and-a-half bash because a) it was more fun, and definitely more cake, than hanging out at a polling place and b) I was trying to get a sense of where the so-called Trump Resistance is really at, on such a critical day in Pennsylvania, where the election results fueled Democratic dreams of gaining a half-dozen or so seats in the magically redistricted Keystone State. That would make us the keystone, as it were, of the Dems' bigger scheme to re-take the U.S. House in January 2019, to call "check" on creeping Trumpism, and maybe even impeach The Donald if things really go South.

Any political momentum that the Democratic primary winners feel going into November's life-or-death midterms owes a gigantic debt to people like the stalwarts of Tuesdays with Toomey, who kept the flame of progressive hope flickering during the darkest months right after Trump was elected.

In early 2017, members of Tuesdays with Toomey and a network of Resistance groups like the Indivisible chapters that popped up around the Philadelphia region educated the newly energized about Trump's travel ban, the fate of the immigrant "Dreamers," and the push to repeal Obamacare — and took to the street to demand action.

This Tuesday, the mood was lighter — less political rally than performance art, as several attendees in mock Met Gala finery mocked Toomey's wealthy campaign donors.

"It's family, it's persistent, and it's not going away," said Mike Hisey, a 55-year-old retail manager and artist, kicking off his "Rebekah Mercer" heels. (He also shows up at GOP rallies dressed as Melania Trump or Kellyanne Conway …"until they kick me out.")  Added Hisey: "And we educate people, and we get people to vote — but we have fun with it."

Yet, amid the laughter, there's a glass-still-half-empty feel that permeates the Trump resistance. A large sign at the rally — "Sen. Toomey, 2689 Days Without a Town Hall in Philly" — is a reminder that the senator hasn't budged on the core demand for public town meetings (though he did hold a restricted, ticketholders-only event in Bethlehem).

The idea of reminding Toomey that he ran in 2016 as a moderate who might occasionally buck Trump seems to have only pushed the senator farther right, as he spearheaded the huge tax cut that largely benefited corporations and the wealthy and is now pushing a plan to gut regulations. The dreamed-for Democratic Congress that took a stutter-step forward on Primary Day would still be seven long months away — plenty of time for Trump to stir up more Middle East chaos, separate more immigrant kids from their parents, and further erode faith in democracy.

For someone like Sylvia Metzler, a retired Philadelphia nurse practitioner who's 80 and has been protesting various injustices for a half century, time is of the essence. She stood up and told the rally about how she was arrested on Monday in Harrisburg, at an event hailing the Poor People's Campaign. "Today I had a tooth pulled," she said. "Tomorrow, I'm getting arrested again!" — at a Philadelphia march calling for an assault weapons ban.

Afterwards, I asked her if the Trump Resistance is moving fast enough to take on Trump. Her vehemence was surprising. "Hell no!" she exclaimed, "because we need more people. I don't think there's a critical mass yet, but we're building for it." Meanwhile, "I just saw in this morning's paper that Trump's approval rating is going up."

A few minutes earlier, the Tuesdays with Toomey-ers had broken into song. "Give my regards to Toomey," they sang. "I'm sure he thought we'd all go away." Their words floated toward the closed windows of the senator's office, competing for bandwidth with blare of car radios and SEPTA buses chugging down Chestnut Street.

Nevertheless, they persisted.

Note: This column was updated with information from Toomey spokesman Steve Kelly on interactions with protesters.