Supreme Court oral arguments on the Affordable Care Act entered their second day Tuesday, with the justices moving from the technicalities of the first day to exploring the legal issues at the heart of whether the law is constitutional or not.

President Obama used humor to downplay a partisan tempest caused by a candid comment to Russian president Dmitri Medvedev that was picked up by an open mic in which Obama said he'll have "more flexibility" in missile-defense negotiations after re-election.

The Environmental Protection Agency was expected to issue on Tuesday the first regulations restricting greenhouse-gas emissions from new power plants. The new standard is expected to be easily met by natural gas-powered plants but would essentially ban new coal-burning facilities since their emissions generally exceed the new limits.

Now that President Obama has made his decision to reject the Keystone XL pipeline, an obvious question is what will it mean for the 2012 presidential election?

Obviously, no one really knows the answer to that though that won't stop weeks if not months of speculation.

The key to Keystone is, which side will have the most success in framing its case to enough voters for it to make a difference?

The president is clearly hoping he can persuade voters that Republicans made him do it, that they gave him no choice by linking a speedy decision by him on the pipeline to their last-minute agreement in December to extend the payroll tax holiday.

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Rep. Don Young (R-AK) during his verbal, mutual smackdown with Rice University historian Douglas Brinkley. A stunned aide watches from behind the congressman.

C-SPAN.org

Rep. Don Young (R-AK) during his verbal, mutual smackdown with Rice University historian Douglas Brinkley. A stunned aide watches from behind the congressman.

One of the nation's best-known academic historians got into a superheated exchange Friday with one of the U.S. House's longest serving members over the issue of drilling in the Arctic National Wildlife Refuge.

Douglas Brinkley, a prolific author and professor at Rice University of Texas, was on a panel of witnesses at a hearing on jobs and drilling in ANWR. Being that Brinkley's latest book is a history of efforts to protect the Alaskan wilderness, he was invited to testify by the committee's Democrats.

Slightly more than a half hour into the hearing, Rep. Don Young, the vinegary congressman who has represented Alaska since 1973, set Brinkley off first by calling his testimony "garbage," then by mistakenly calling him "Mr. Rice."

BRINKLEY: "It's Dr. Brinkley, Rice is a university. I know you went to Yuba College and couldn't graduate..."

YOUNG: Well, I called you Dr. Rice. I'll call you anything I want when you sit in that chair. You just be quiet. You be quiet.

BRINKLEY: You don't own me. I pay your salary.

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Actress Daryl Hannah with other anti-Keystone XL protestors at the White House in August 2011.

Evan Vucci/AP

Actress Daryl Hannah with other anti-Keystone XL protestors at the White House in August 2011.

The 2012 presidential election could be close, with President Obama needing support from every segment of his political base to win re-election.

So the president's move (made through the State Department) to delay his controversial decision on the Keystone XL pipeline until beyond Election Day 2012 isn't really a shocker. The White House, for the record, denies that politics played a role in the decision.

Environmentalists opposed to the project which would construct a 1,700-mile pipeline to transport oil from Canada's Alberta tar sands region to refineries in the U.S. and ports on the Gulf of Mexico, recently protested en masse at the White House.

The protests involving thousands were meant as a last-minute reminder to the White House of the political risks the president ran if he approved the pipeline despite such concerns.

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Mitt Romney.

JIM WATSON/AFP/Getty Images

Mitt Romney.

Mitt Romney drew barbs Friday for his continued shift to the ideological right on the climate change issue.

Actually, the criticism for Romney that blew in from both the political right and left came as critics accused him of a full flip flop on global warming.

Romney's political foes jumped on comments he made in Pittsburgh Thursday at a campaign appearance.

My view is that we don't know what's causing climate change on this planet. And the idea of spending trillions and trillions of dollars to try to reduce CO2 emissions is not the right course for us.

That contradicts to a degree what Romney said in his book "No Apology" published this year.

I believe that climate change is occurring—the reduction in the size of global ice caps is hard to ignore. I also believe that human activity is a contributing factor.

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President Obama tours the ill-fated Solyndra, May 2010.

Paul Chinn/AP

President Obama tours the ill-fated Solyndra, May 2010.

Updated, Sept. 30, 2011 at 10:24 am with Energy Dept. response -

It obviously seemed like a good idea at the time to some Obama administration officials to have a major fundraiser for the president working inside the Energy Department to supervise the career employees who reviewed the applications for federally backed green-energy loans.

In hindsight, however, especially after the failure of solar-panel maker Solyndra which received a $535 million loan and the attendant scrutiny, the administration clearly opened itself up for criticism and suspicions of wrongdoing.

A report by ABC News and the Center for Public Integrity on the ties between the fundraisers and the Energy Department loan program underscores the point.

While there has been no publicly disclosed evidence of illegality, at the very least there is certainly the problem of appearances.

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Firefighting helicopters dump water and flame retardant after loading up with water from a pond at Lost Pines Golf Club as they fight a fire in Bastrop State Park on September 6, 2011 in Bastrop, Texas.

Erich Schlegel/Getty Images

Firefighting helicopters dump water and flame retardant after loading up with water from a pond at Lost Pines Golf Club as they fight a fire in Bastrop State Park on September 6, 2011 in Bastrop, Texas.

Rick Perry heats up the atmosphere every time he talks about climate change. He's an avowed global warming doubter who once quipped, "The biggest source of carbon dioxide is Al Gore's mouth."

Perry set off the debate again in New Hampshire recently when he said, "I think we're seeing weekly, and even daily, scientists who are coming forward and questioning the original idea that manmade global warming is what is causing the climate to change."

He went further in his book, Fed Up: "The complexities of the global atmosphere have often eluded the most sophisticated scientists."