But his mind is still on the crossword. Photo: Jacquelyn Martin/AP/Shutterstock

Senate Republicans make a terrible studio audience for the taping of a live television show.

The first day of oral arguments allotted to the House managers was clearly not intended for those inside the Senate chamber. They laid out a chronology of the Ukraine scandal and unveiled their factual case for why they believe President Trump abused his power and should be removed from office. It featured constant repetition: At least one video clip was aired in the chamber three different times, in which Trump urged both Ukraine and China to investigate the Bidens. There were a number of appeals for the Senate to subpoena witnesses and documents — the day after 11 different attempts to do so were voted down according to party lines. In short, it was perfect for a television audience of Americans flipping channels and not paying constant attention.

Like much of the country, many of the senators were tuning in and out as well.

Senate Republicans flashed in and out of the cloakroom and engaged in various distractions. Broad gaps appeared in their rows of desks as the day stretched on. Lindsey Graham used the chair of his neighbor in the chamber, Jerry Moran, to rest his arm for much of the day because the Kansas Republican was absent. Wyoming Republican John Barrasso roamed the floor and chatted with colleagues. A cell phone even went off on the floor, a violation of the stern taboo of senators possessing electronic devices during the trial.

Some were studious though. Susan Collins and Lisa Murkowski, moderates who sit next to each other, spent much of the session in their seats paying attention. Marco Rubio took notes for much of the day in binders sprawled across his desk. Ohio Republican Rob Portman was just as attentive, taking occasional breaks to stand behind his desk, taking notes while doing so and promptly buttoning his jacket every time he stood up.

The contrast among the Republicans was best displayed by Utah Senator Mike Lee and Kentucky Senator Rand Paul, arch-conservative neighbors in the chamber. Per an aide, Lee brought two books with him: Impeachment in America From 1635 to 1805 and The Federalist Papers. In contrast, Paul entered the chamber with a crossword puzzle that he placed on his desk.

Democrats were not the model of decorum either, after the first day of the trial ran until nearly 2 a.m. Early in the afternoon, Mark Warner appeared to doze, his head resting in his hand. Others left their desks to follow the proceedings standing up; Cory Booker and Michael Bennet were particularly inclined to stretch their legs throughout the session. At one point, Warner was seen pointing toward the audience in the gallery. He gestured toward Bennet to look in a specific spot that seemed to be where actress Alyssa Milano was watching the proceedings.

Democrats did find entertainment elsewhere in the chamber. At the end of the night, Democratic senators laughed at several of Adam Schiff’s sarcastic jibes at the Trump administration for withholding documents. The day started with Schiff getting laughs for a more innocent joke. After quoting Alexander Hamilton, he noted the Founding Father’s “recent return to celebrity,” a reference to the musical Hamilton. The statement provoked a broad smile from Bernie Sanders.

Senators seemed to find the most comfort in food as they tried to endure the long day. A bag from the fast-casual Mediterranean chain Roti could be spotted in the Democratic cloakroom and a number of senators could be seen munching on candy on the Senate floor. Two Republican senators, Tom Cotton and Richard Burr, even indulged in the Senate precedent allowing glasses of milk on the floor: Cotton drank one glass while Burr downed two during the afternoon.

The only jolt of excitement during the day was when a spectator in the gallery briefly burst out shouting about “Jesus Christ” before being quickly arrested by Capitol Hill police. The sudden noise sparked senators to run back on to the floor to discover what the commotion was. It was understandable. The lone protester may not have amounted to much but, unlike the House managers, he was entirely focused on getting the senators’ attention.

Correction: A previous version of this article stated that the phone belonged to Senator Ted Cruz. A spokesperson for Senator Cruz has since informed New York that he did not bring his phone on the floor.