(Sarah Parnass/The Washington Post)

Sen. Sherrod Brown (D-Ohio) didn’t hesitate.

“I’m going,” he said of Friday’s inaugural ceremonies for President-elect Donald Trump.

“I want to be there,” Brown said. His presence would “remind” Trump and other Republicans of the fights ahead on banking, civil rights and other issues on which there is a deep divide with Democrats.

“I will be there as well,” Sen. Elizabeth Warren (D-Mass.) chimed in during a conference call Tuesday about the potential for Trump to dismantle the Consumer Financial Protection Bureau.

Those views, from two Democrats considered for the 2016 vice-presidential nod, have been echoed by other leading Senate liberals. Over the weekend, Sens. Cory Booker (D-N.J.) and Bernie Sanders (I-Vt.) also pledged to attend Trump’s inauguration while vowing to keep up the fight against his policies in the Capitol.

Preparations for Friday’s inauguration continue at the U.S. Capitol. (Patrick Semansky/AP)

So far, not a single Senate Democrat has joined nearly 60 House Democrats, almost a third of their entire caucus, who have vowed to boycott Trump’s swearing-in. Those House Democrats have pledged solidarity with Democratic Rep. John Lewis (Ga.), who prompted a Twitter war with Trump over the weekend after declaring that Trump will not be a “legitimate president” in part because of Russian interference in the 2016 campaign.

Lewis’s declaration became a galvanizing call on the left, for whom the civil rights icon has always been a hero. Liberal activists vaulted Lewis’s autobiography up the charts of online book merchants. They jeered Trump. They cheered for the boycott.

But none of it has translated into similar action at the other end of the Capitol.

Senate Democrats represent far broader numbers of people and have to be respectable and responsive to, in most cases, millions of their constituents who voted for Trump. And 25 of them are up for reelection in 2018. “So there are 25 senators who probably think it’s risky,” said Rep. John Yarmuth (D-Ky.), who will join Lewis’s boycott.

Brown plans to be a loud voice opposing Trump’s efforts to dismantle key portions of the Dodd-Frank law regulating Wall Street — but he also hails from Ohio, where Trump routed Democrat Hillary Clinton in the largest victory in the Buckeye State since 1988. Brown will need to win over voters who cast ballots for Trump to win reelection.

The issue is trickier for Senate Democrats with clearer national ambitions. Last week, Booker sat next to Lewis as both testified against Sen. Jeff Sessions’s nomination to be attorney general, citing the Alabama Republican’s record on civil rights issues. Senate colleagues accused Booker of launching his 2020 presidential campaign.

Yet he won’t be at Lewis’s side on Friday; he will be on the Capitol terrace not far from President Obama and Trump.

“I respect everybody’s choice in this,” Booker told reporters in New Jersey. “My personal feeling is this is the peaceful transition of power.”

Warren’s most extensive public comments came with members of the Boston press corps after an event honoring Martin Luther King Jr.’s birthday. She reiterated her plan to attend the inaugural but ducked the issue whether Trump was a “legitimate president.”

“What I agree with is that John Lewis is a man who has earned the right to have his view of Donald Trump’s presidency and legitimacy,” she said.

House Democrats have joined Lewis for a variety reasons. Yarmuth said Trump was “legally elected” and would be a legitimate president, but he could not support Trump’s behavior before and after the election.

“You have to show respect for the office,” he said.

It’s not the first time this month that Senate Democrats have disappointed their more activist House colleagues.

Just two weeks ago, during the official tally of the electoral college, House Democrats repeatedly lodged complaints regarding Russian interference, voter access to polling places and other allegations.

But no senator joined the protest; as a result, the objection could not even be considered under the complex rules of the electoral college. “It’s over,” said Vice President Biden, who presided at the event.

Lewis took the attack on Trump to a higher level during an interview taped Friday with NBC’s “Meet the Press.”

“The Russians participated in helping this man get elected. And they helped destroy the candidacy of Hillary Clinton. I don’t plan to attend the inauguration,” Lewis told host Chuck Todd.

Lewis, an original Freedom Rider who was beaten and arrested during civil rights protests in the 1960s, has long been considered a moral compass for House Democrats, if not the entire chamber.

When Democrats faced thousands of protesters over the Affordable Care Act in 2010, they put Lewis at the front of their line, a gavel in hand, and marched from an office building into the Capitol for the final hours of debate.

Last summer, as House Speaker Paul D. Ryan (R-Wis.) held off on debate over gun legislation, Lewis became the emotional leader of an overnight sit-in that still angers Republicans.

The response didn’t slow him down.

Todd asked Lewis whether Democrats should work with Trump on any issue. “Well, it’s going to be very hard and very difficult,” he said. “Almost impossible for me to work with him.”

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