LONDON — Flying the giant Trump baby balloon once again, Britons protesting President Trump’s state visit tried to bring central London to a standstill on Tuesday with demonstrations that they hoped would draw large crowds throughout the day.

But the turnout fell below expectations and the volume of the protests during Mr. Trump’s first visit in July, suggesting that the passions that drove hundreds of thousands into the streets then have now cooled somewhat.

Though not, perhaps, among those who showed up on Tuesday.

“Stop Racism, Stop Trump,” one placard read.

“Climate change is real, your tan is not,” read another.

Many wore caps that mocked the president’s 2016 campaign slogan, “Make America Great Again.” Theirs read: “Make America Great Again. Impeach Me.”