Despite former vice president Joe Biden’s continued lead in the polls, it seems that the 2020 Democratic contender giving the Trump campaign the most concern right now is Sen. Elizabeth Warren. There’s a variety of reasons for the growing attention paid to Warren, and she’s had a strong share of early gaffes and campaign stumbles back in late December of last year into January of this year.

However, she managed to weather her early mistakes and has been consistently pushing a populist liberal campaign message and continuing to build her support as other candidates start to falter.

Business Insider now says that Warren is the candidate getting the most attention inside the Trump 2020 reelection campaign:

Trump, who frequently derides Warren as “Pocahontas,” is apparently convinced he can “hate-tweet her away,” but his advisers don’t share that view.

They also “see her ability to capitalize on the populist/outsider energy he ran on in 2016 and has tried to recreate despite holding office,” Haberman wrote.

Warren approaches voters with a left-wing populism to contrast the President’s right-wing populism. In some ways, the messages overlap with the same tone of one group of the population pushing back against another group. For Trump, it’s the working-class voters pushing back against the political class and leadership in Washington, an anti-establishment message. For Warren, it’s the same working-class voters she’s appealing to, but instead of an anti-Washington message, it’s an anti-establishment message aimed at the wealthy, the “one-percenters” of society where the most wealth is concentrated.

The other part of the equation that Business Insider sees is Warren’s status as a so-called “compromise” candidate since her support overlaps with several other Democratic campaigns:

Warren has seen a meteoric rise in a narrowing Democratic field over the past several months. Most recently, three 2020 candidates dropped out within a week of one another: New York Sen. Kirsten Gillibrand, Washington Gov. Jay Inslee, and Rep. Seth Moulton.

The development could be a boon for Warren, according to Insider polling, which suggests Warren is best positioned with each candidate’s base to capitalize on their departures from the race.

She also overlaps considerably with the bases of Sen. Bernie Sanders of Vermont and former Vice President Joe Biden. Insider polling found that 50% of Biden supporters and 57% of Sanders supporters would also be happy with Warren as the Democratic nominee.

This is a trend that we pointed out back in June, that Warren appears to be lining up as strong choice to be a compromise candidate bridging the moderate and progressive wings of the Democratic Party. The other point worth noting is that Warren’s support has grown steadily rather than impulsively, which is in contrast with candidates like Sen. Kamala Harris. As a result, Warren’s support has been stable while Harris shot up after the first debate, only to crater back into single-digits a month later.

The Daily Beast also notes, in a related story, that the Trump campaign has been working to push out negative opposition research stories against Warren, but nothing has seemed to drag her down all that much:

“We all push out the bad Warren stories but they don’t go very far,” one Republican strategist said.

The frustration Republicans are beginning to feel about Warren’s non-stick nature was picked up repeatedly in interviews with 10 Republicans, including Trump campaign and White House officials, associates of the president, and other GOP operatives with knowledge of the situation. These sources stressed that the anti-Warren effort within GOP circles hadn’t fallen off since the DNA snafu. Indeed, everyone from officials on Trump’s 2020 re-election campaign, to the Republican National Committee, to a select group of opposition researchers have been sifting through her record in search of vulnerabilities. But with few punches landing, the worry is that Trump may have already taken his best shot, and that Warren will end up looking increasingly formidable for having bounced back.

President Trump personally admitted that he was fearful he had fired off his best Warren mockery too early in the campaign. At a campaign rally in New Hampshire, the President addressed the topic:

“I did the Pocahontas thing. I hit her really hard, and it looked like she was down and out, but that was too long ago,” Trump said. ”I should have waited. But don’t worry, we will revive it. It can be revived. It will be revived. And it can be revived very easily, and very quickly, and we’re gonna have some fun in the state of New Hampshire.”

Warren walked into some major unforced errors with the DNA test attempting to prove Native American heritage. The test results fell flat, and she was forced to apologize to the Cherokee Nation since they view DNA testing as an offensive way to claim tribal membership.

However, that’s all in the past now, it’s old news in this 24-hour campaign we live in. Even 24-hours is generous, perhaps a 12-hour news cycle is more accurate. The President can revive his attacks about Warren’s heritage, but will it matter? Her mistakes are baked into the campaign now and she has attempted to get out in front of the issue and get it out of the way.

From the President’s view, Elizabeth Warren is not a Bernie Sanders, and she’s not a Joe Biden. She’s much more strategic and polished with regard to policy proposals and specifics. If she continues this run in the Democratic primary showing no signs of stumbling, look for a new line of attack from the President’s campaign and allies that hits her for something other than the “fake Indian” meme.