Senate Republicans refusing to countenance filling the US supreme court vacancy have, so far, been able to make it a debate about abstract concepts. But when Barack Obama names his nominee, that is set to change.

“They just keep digging themselves in a deeper and deeper hole,” Democratic senator Chuck Schumer said on Tuesday. “If anything, when the president nominates someone and there’s a real live person there, and I’m sure that person will be a very reasonable person to be on the court in the American people’s eyes, it’s going to get worse for them. It’s not going away.”

The Republicans might find they have a harder case to make in the court of public opinion if, for example, Sri Srinivasan, touted as a favourite among several strong contenders, gets the nod. Chris Coons, a Democratic member of the Senate judiciary committee, described him as “balanced” and “capable”.

Srinivasan, who turned 49 on Tuesday, has enjoyed a stellar career. He was born in India and migrated with his family to the US in the late 1960s.

He graduated from Stanford and lectured at Harvard. As a lawyer, one of his most high-profile cases was the defence of Jeffrey Skilling, the former Enron executive. As deputy solicitor general of the US, he argued 25 cases before the supreme court.

Crucially, he was nominated by Obama to the powerful US court of appeals for the District of Columbia circuit and was confirmed by the Senate in 2013 by a 97-0 vote. Republicans would therefore have to explain why, having approved him once, they are unwilling to consider him now.

Edward Fallone, associate law professor at Marquette University Law School in Milwaukee, described Srinivasan as an “excellent candidate” for several reasons: his current position on a court that handles many cases involving administration actions; his previous approval by the Senate; his service under both Democratic and Republican administrations; and the historic importance of appointing the first Asian American to the supreme court.

“It will erase any arguments as to the merit of his nomination and reveal whether the Senate is being obstructionist, period,” he said.

Republicans emerged from a closed-door meeting on Tuesday to announce that they would not vote on any Obama nominee to the supreme court, nor even hold a committee hearing on a nominee to replace Justice Antonin Scalia, who died earlier this month. The majority leader, Mitch McConnell, claimed that not since 1888 has a vacancy created in a presidential election year led to a nominee being approved by the Senate controlled by a different party.

But Srinivasan’s bipartisan credentials could make the argument harder to maintain. He clerked for former Justice Sandra Day O’Connor, a Republican. At his 2013 Senate confirmation he was described by Ted Cruz, now blamed along with Donald Trump by Democrats as the cause of the intransigence, as an old friend. He has even been criticised by environmental groups for cases in which he defended oil giant ExxonMobil and the mining company Rio Tinto – hardly typical leftwing causes.

Even conservative lobbyist Curt Levey, executive director of FreedomWorks Foundation, said: “Sri Srinivasan has as good a chance as anyone. He was confirmed unanimously by the Senate; Ted Cruz seemed to like him. If I had to guess, I’d say the president will nominate Sri or a senator.”

Washington lobbyist Vincent Eng, whose clients include the National Asian Pacific American Bar Association, offers advice to the White House during the nominating process and knows Srinivasan personally. “At every stage of his career he’s demonstrated he’s a top shelf candidate,” he said. “He’s a great consensus builder, an excellent candidate … He’s a great basketball player as well.

“I think his record stands on its own. He has bipartisan support; I don’t think anyone can doubt that. Every single senator who was in the Senate that day [in 2013] voted for him, so it would be tough for them to say why he is not suitable for the supreme court.”

Eng added: “Sri is one of the smartest individuals I’ve ever met. Incredibly humble and incredibly thoughtful. He remembers when your birthday is and sends you a note. His name is still ‘Sri’, it’s not ‘Judge’. He’s an individual I respect immensely.”

Srinivasan also has a compelling life story that resonates in a nation of immigrants. Accepting a 2013 India Abroad Person of the Year award, he told an audience: “When we became citizens, we took an oath to support and defend the constitution and laws and bear faith and allegiance to the same. When I became a judge last year, I took the very same oath administered by Justice O’Connor.

“Rather amazingly, I’m now in the position to administer that oath to others who themselves are becoming citizens … What a profound statement about the opportunity in this country. What a profound privilege to go from one who took the oath from a judge to one who now is in the position to administer the oath as a judge.”

Obama, whose presidency has been plagued by clashes with Congress, has said he will go ahead with a nomination, insisting that it is his constitutional duty. The stakes are high with the supreme court split between conservatives and liberals.

But if he is seeking a judge who has previously been confirmed by the Senate, Srinivasan is not his only option. Other contenders include Merrick Garland, Patricia Millett and Robert Wilkins of the US court of appeals for the District of Columbia circuit and Jacqueline Nguyen and Paul Watford of the US court of appeals for the ninth circuit.

The attorney general, Loretta Lynch, is also rumoured to be in the frame but the long Senate wrangle over her appointment to that position could be an ominous sign.

Conservative pressure groups remain adamant. Carrie Severino, chief counsel and policy director of the Judicial Crisis Network, said of Obama: “In the past he’s presented people as moderate but they turned out not to be. It makes sense to wait for the election and let the people have a say on these issues.”

A veteran lobbyist, who did not wish to be named, said: “Sri would be a fantastic judge. But we have a very nasty Republican frontrunner who would be certain to mock his first name and the fact he was born outside the country.

“I don’t think Sri or anyone else has a good chance of being nominated. We have a deeply coarsened culture of disruption in Congress. This has gotten nasty.”