Good morning and welcome to On Politics, a daily political analysis of the 2020 elections based on reporting by New York Times journalists.

Where things stand

• Hillary Clinton mostly sat out the primary campaign, dipping back in momentarily to give interviews around the January release of a Hulu documentary series about her life, and to toss a few jabs at Bernie Sanders. But on Tuesday she returned to center stage to endorse Joe Biden in what is quickly becoming a genre unto itself: the split-screen endorsement video. She and Biden spoke for 50 minutes about women’s issues during the coronavirus pandemic. (Neither mentioned the fact that Biden is facing an increasingly high-profile allegation of sexual assault, which he has denied.) The virus, Clinton said, “is having a disproportionate impact on the front lines: on women working, on women caring for others, on women holding down the home as we go through this together.” She added, “Just think of what a difference it would make right now if we had a president who not only listened to the science, put fact over fiction, but brought us together.”

• While President Trump has appeared before news cameras almost every day throughout the pandemic, Biden hasn’t made a single major speech since last month. Only in the occasional endorsement video — which he films from a makeshift TV studio in his basement — does he outline his own proposals. Speaking to Clinton, Biden rattled off a battery of policies that he would embrace to confront the virus’s effects, including expanding programs to keep workers employed, freezing rents, halting foreclosures and making more food stamps available. As in other recent conversations, Biden made a point of saying that he didn’t just want to return to a pre-virus, pre-Trump status quo. “While we need to do all we can to help women and families get through this crisis, when we get to the other side,” he said, “we can’t just build back to where we were before. We have to build a much more inclusive, much more equitable middle class and an economy that everybody, everybody, gets a fair shot at.”

• The Senate is always a glacial body, but Democrats in the minority are getting impatient for more action on virus relief. They’d like to conduct some oversight on the officials in charge of the crisis response, too. Chuck Schumer, the minority leader, and his Democratic colleagues said so in a letter they sent on Tuesday to Mitch McConnell, the majority leader. The letter noted that McConnell had not put any virus-related oversight hearings on the Senate calendar, nor any “legislative or committee business related to the Covid-19 public health and economic emergencies.” Instead, after passing a series of relief bills, McConnell is seeking to return the Senate to one of his favorite tasks: confirming conservative judicial appointees. One of those is McConnell’s own 38-year-old protégé, Justin Walker, whom Trump recently nominated for a seat on the powerful District of Columbia Court of Appeals.

• In the presidential race alone, roughly $100 million has already been spent on Facebook ads. And with people largely stuck inside — and often glued to their screens — online advertising has never been more important. This cycle, as Nick Corasaniti reports, Democrats have a crucial ally in the digital fight: James Barnes, who as a former Facebook employee was embedded in the Trump team in 2016, and was later named an “M.V.P.” of the campaign. He came up with a program titled “Barometer” that allows campaigns to test their messages with Facebook users in real time by distributing surveys. And he has been putting it to use in coordination with Pacronym, a Democratic super PAC.

Photo of the day

President Trump met with Gov. Ron DeSantis of Florida and Dr. Deborah Birx, the White House coronavirus response coordinator, in the Oval Office on Tuesday.

Justin Amash, the anti-Trump ex-Republican, is mulling a Libertarian presidential run.

In the lead-up to the 2016 presidential election, with many conservative voters still wary of Trump’s candidacy, the Libertarian candidate Gary Johnson shot to double digits in polls as late as mid-September.

Then he fizzled, winning just 3 percent of the vote as Republican voters came home to support their party’s nominee.

But what would happen in 2020, after a full term of Trump in the White House, if another credible Libertarian candidate ran against him? We may soon find out.

Justin Amash, a 40-year-old congressman from Michigan who switched his registration from Republican to independent last year out of unease with Trump’s takeover of the Republican Party, announced last night on Twitter that he had formed an exploratory committee toward a run for president as a Libertarian.

On a new website, “Amash for America,” his language was bold: “We’re ready” was emblazoned across the home page.

Amash, a five-term congressman, would need to win the Libertarian Party’s nomination at its convention, which is scheduled to take place next month in Austin, Texas — though those plans have been thrown into jeopardy by the pandemic. Nicholas Sarwark, the national chairman of the Libertarian Party, told our reporters Jonathan Martin and Alexander Burns that he thought Amash would be a formidable contender for the nod.

Trump has further consolidated his support among Republicans since taking office; he now enjoys a 93 percent nationwide approval rating among members of his party, according to Gallup.

But his approval rating among conservatives is noticeably lower — 77 percent — and among independents it is a dismal 39 percent. Those are key demographics from which Amash would be looking to pick up support.

Should a Libertarian candidate peel off a significant number of votes, it is not necessarily clear whether it would do more to help the president, by siphoning anti-Trump conservatives away from Biden, or if it would hurt Trump by absorbing voters who might otherwise have reluctantly supported him.

The results of the 2016 election do little to clear this up. In exit polls, Democrats and Republicans were about equally likely to say they had refrained from voting for either Clinton or Trump. Most third-party supporters identified as independents.

In Michigan, Amash’s home state, where Trump’s narrow victory helped send him to the White House, Johnson picked up 3.6 percent of the vote. If even one in 10 of Johnson’s supporters in Michigan had voted for Clinton instead, she would have won the state.

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