The Note: Trump creates fresh health care mess for GOP The administration's leading an effort to have Obamacare ruled unconstitutional.

The TAKE with Rick Klein

Candidates don't always get to run on the issues they want to. And sometimes they do get the issues they want -- even if those around them may wish otherwise.

That's the scenario confronting President Donald Trump now on health care, with arguments teed up for Tuesday in a federal appeals court in New Orleans.

The Trump administration is leading an effort to have all of Obamacare -- yes, even preexisting conditions -- ruled unconstitutional, after a judge in Texas ruled in their favor late last year.

Another legal victory for the administration would be a win for a GOP base that's long treated Obamacare as a curse word -- or worse. But until, or unless, the president unveils his promised "phenomenal" health care plan, it would be a win that's widely viewed as a political loss for the Republican Party.

Just 38% of Americans overall and 41% of independents approve of the job Trump is doing on health care, according to the latest ABC News/Washington Post poll. GOP leaders on Capitol Hill have made clear they want to fight on more favorable terrain next year.

On Monday, the president held a public event to sing his own administration's praises on environmental issues -- an area where the public stands with Democrats even more firmly than on health care.

The president may hope his words and promises make up for any perceived policy shortcomings. But his administration could be forcing an awkward new reality on voters -- just in time for 2020.

The RUNDOWN with MaryAlice Parks

Rep. Eric Swalwell, D-Calif., told former Vice President Joe Biden it was time for more senior members of the Democratic Party to "pass the torch" to younger members like him.

But now, two weeks later, it's Swalwell's presidential campaign that has flamed out.

"After the first Democratic presidential debate, our polling and fundraising numbers weren't what we had hoped for, and I no longer see a path forward to the nomination," he told his supporters on Monday.

He was at risk of being left out of the next debate later this month, and with so many Democratic candidates struggling to register in the polls at all, others might soon find the pressures to break out too tough to justify their candidacies.

Biden and Sen. Bernie Sanders, I-Vt., are still comfortably ahead, and Sen. Elizabeth Warren -- as further evidence of her rise in popularity -- raised a total of $19.1 million in the second quarter. That's more than three times what her campaign raised last quarter.

Campaign launches may not be finished, however, even this late in the game. Billionaire and climate activist Tom Steyer is, according to the Atlantic, still flirting with the possibility of making a run.

Editor's note: Hours after "The Note" was published, Steyer, who earlier this year said he would not pursue the Democratic nomination for president, reversed course on Tuesday and announced his campaign for president.

The TIP with Quinn Scanlan

Had Swalwell continued in the race, his campaign was likely to be on life support. His chances of being booted from the second debates this month were increasing by the poll.

"We have to be honest about our own candidacy's viability," he said Monday.

Twenty-one candidates are currently qualified for the second round of debates in Detroit, based on the Democratic National Committee's rules -- and Swalwell was among them.

But with the DNC's self-imposed cap of 20 participants and Swalwell capturing only 1% support in three polls, Montana Gov. Steve Bullock, who has accrued 1% in five polls so far, was expected to bump the California congressman from the stage, according to the tie-breaker rules.

With the deadline to qualify by polling only one week away now, Swalwell's chances of making up ground seemed slim, but those chances seem even slimmer for candidates who have yet to qualify: Miramar, Florida, Mayor Wayne Messam, who has two qualifying polls, former Sen. Mike Gravel, D-Alaska, who has one qualifying poll and Rep. Seth Moulton, D-Mass., and former Rep. Joe Sestak, D-Pa., who each have zero qualifying polls.

THE PLAYLIST

ABC News' "Start Here" podcast Tuesday morning's episode features ABC News Chief National Affairs Correspondent Tom Llamas, who breaks down the indictment brought against billionaire Jeffrey Epstein on Monday. And ABC News' Conor Finnegan explains why Iran's latest uranium announcement has some national security officials concerned. http://apple.co/2HPocUL

ABC News' "Powerhouse Politics" podcast Bud Selig, former MLB commissioner, joins ABC News Political Director Rick Klein for a special edition of the podcast, recorded the week of MLB's All-Star Game. Selig talks about his working relationship with several politicians and talks about the one time he dropped an f-bomb on a sitting vice president during a tense meeting at the White House. https://bit.ly/2FA0CIm

ABC News' "The Investigation" podcast On this episode of "The Investigation," President Donald Trump's personal attorney, Jay Sekulow, talks with ABC News Senior Editorial Producer John Santucci and White House and Capitol Hill Reporter Katherine Faulders about congressional investigations. Sekulow also discusses the ongoing legal battles for the president's tax returns. And, when asked by "The Investigation" about Robert Mueller's upcoming testimony on the Hill, he said, "They're just looking for the gotcha moment. I don't see it." https://bit.ly/2FMgHe3

WHAT YOU NEED TO KNOW TODAY

President Donald Trump and Vice President Mike Pence welcome the emir of Qatar to the White House for a bilateral meeting, commercial signing ceremony and then an expanded working lunch.

A Republican primary runoff election will be held for North Carolina's 3rd Congressional District. Polls are open from 6:30 a.m. to 7:30 p.m. The winner will compete in September's special election to replace the late Republican Rep. Walter Jones, who died in February.

Sen. Kirsten Gillibrand, D-N.Y., participates in "Politics and Eggs" at the New Hampshire Institute of Politics in Goffstown, New Hampshire.

Rep. Tim Ryan, D-Ohio, hosts several meetings in South Carolina and ends the day with a fundraiser for a state house candidate in Greenville.

Montana Gov. Steve Bullock is in Iowa and tours an ethanol facility in Gowrie, a co-op in Rippey and hosts a house party in Des Moines.

Marianne Williamson has a community meeting dinner in Orangeburg, South Carolina.

Download the ABC News app and select "The Note" as an item of interest to receive the day's sharpest political analysis every weekday.

The Note is a daily ABC News feature that highlights the key political moments of the day ahead. Please check back tomorrow for the latest.