Morning Must Reads: Aug. 3

President Obama is unveiling a new climate change plan to limit power plant emissions today that is already becoming the subject of controversy on the 2016 campaign trail. Hillary Clinton quickly endorsed the rule, as Republicans lined up to oppose it. In Dana Point, California, this weekend, five GOP presidential contenders gathered to pitch themselves to the Koch Brothers’ political network, including hundreds of well-heeled donors. And though he wasn’t invited, GOP front-runner Donald Trump still loomed large over the event, as candidates struggle with his rise in the polls.

In advance of this week’s GOP debate, 14 candidates will take questions tonight at a New Hampshire Union Leader Forum. A series of new polls released in the next 34 hours will determine who makes the cut in Cleveland on Thursday, as Republican candidates complete a blitz of Fox News and other nationwide media in hopes of getting their poll numbers up.

And amid reports he is now leaning toward running, aides said Vice President Joe Biden is still considering a 2016 bid. But a decision is not expected for more than a month and the VP has personally sent few signals either way about his intentions. Should he get in, he would instantly claim about 15 percent of the Democratic vote, according to recent polling, but his path to topple Clinton remains unknown.

Here are your must-reads:

Uninvited Donald Trump Crashes Koch Retreat in Spirit
His shadow looms large over donor retreat, TIME’s Philip Elliott reports

The Left’s Quest to Create Hundreds of Elizabeth Warrens
TIME’s Sam Frizell reports on progressives eyeing down-ticket races

As Joe Biden Resumes Official Work, So Does Talk About a 2016 Run
No decisions yet [Los Angeles Times]

Obama’s New Climate-Change Regulations to Alter, Challenge Industry
Already a divisive 2016 issue [Wall Street Journal]

Sound Off

“If people don’t like it, that’s just tough luck.” — Former Florida Gov. Jeb Bush on his record fundraising haul

“Quite a few members of this field have attacked Donald Trump. A lot of folks in the media have asked me ‘Ted Cruz, will you do the same?’ I have been glad to praise Donald Trump for speaking out boldly and brashly and for focusing on illegal immigration.” — Texas Sen. Ted Cruz

Bits and Bites

Ted Cruz Says Climate-Change Fears Falsified by Scientists and Politicians [TIME]

Hillary Clinton Praises Mother in First TV Ads of 2016 [TIME]

Iowans to Chris Christie: Take It to Donald Trump [Des Moines Register]

Scott Walker Still Isn’t Sure If President Obama Is Christian [TIME]

Hillary Clinton Releases Eight Years of Tax Returns [TIME]

Jeb Bush’s Camp Sees an Upside to Donald Trump’s Surge in the G.O.P. [New York Times]

Doctor: Hillary Clinton In ‘Excellent’ Physical Condition [TIME]

Sen. Graham Moved Up in Air Force Reserve Ranks Despite Light Duties [Washington Post]

Bush Rolls Out Six-PointPplan to Address Border Security, Illegal Immigration [WMUR]

Obama Had a $3 Golf Bet with House Democrats. Guess Who Won. [Washington Post]

RNC Set to Vote on Anti-Gay Resolutions at Summer Meeting [Washington Blade]

John McCain in New Hampshire: ‘Lindsey Graham, He’s My Man!’ [Washington Post]