WASHINGTON — President Barack Obama seemed to call Hillary Rodham Clinton’s idea of a no-fly zone in Syria “half-baked.”

Clinton described the president’s immigration strategy as “harsh and aggressive.”

And as Obama tries to rally Democrats around the chief economic proposal of his second term, the party’s presidential front-runner has stayed conspicuously silent.

With Clinton looking for ways to distinguish her ideas from those of her former boss, their relationship has grown increasingly complicated.

No issue presents more potential for friction than trade.

For months, Clinton has resisted weighing in on the Trans-Pacific Partnership, which has divided the Democratic base. Now that negotiations have concluded, Clinton soon will be forced to choose between supporting the president on a legacy-enhancing issue or siding with labor unions, environmentalists and other liberal constituencies that oppose the deal.

“I’m going to be talking to people. They’re getting me all the information they can gather so I can make a timely decision,” Clinton said Tuesday in Iowa.

The awkward dynamic isn’t a surprise. Clinton’s campaign and the Obama administration have always said the time would come when she would outline her own policies and deliver criticisms, implied and direct, of Obama.

“I am not running for my husband’s third term or President Obama’s third term,” Clinton told voters in Davenport, Iowa, repeating a frequent line from her campaign speeches. “I’m running for my first term.”

While she frequently commends the president, Clinton has been offering critiques of his policies more and more.

Last month, she came out against the Keystone XL pipeline, which would carry oil from Canada to the U.S. Gulf Coast; the administration remains undecided.

In August, she said Obama’s decision to approve offshore drilling in the Arctic wasn’t “worth the risk” to the environment. She subtly resurrected her 2008 primary attack of Obama’s approach to world affairs, taking a more hawkish stance toward Russia, Syria and Iran.

On both immigration and gun control, she has pledged to use her executive power to do more than Obama.

Citing Obama’s deportation policy, Clinton said this week, “I’m not going to be breaking up families. And I think that is one of the differences.” She added, “But I totally understand why the Obama administration felt as though they did what they did under the circumstances.”

Campaign veterans in the White House say the impact of Clinton’s one-upping is minor and they dismiss some of her proposals as routine campaign fodder. Candidates use policy plans to declare their priorities. Worries over practical implementation come later.

Trade falls into a different category. If Clinton opposes Obama’s deal, she could undermine his arguments just as the White House is in the final stretch of a deal years in the making.

Clinton’s main challenger, Vermont Sen. Bernie Sanders, says the accord is “disastrous,” so Obama may be in the uncomfortable position of watching a Democratic debate next week in which none of the major candidates is willing to defend the deal.

Clinton aides know she must tread lightly when it comes to criticizing Obama, given that much of her strategy relies on the still-loyal coalition of African-Americans, Latinos, women and younger voters that twice elected Obama. But at the same time, they say she must find ways to distinguish herself — and undercut Republican attacks that Clinton would simply be a third Obama term.

Many of Clinton’s top aides joined her campaign from the White House and the two staffs remain in frequent communication.

Before Clinton announced her opposition to the Keystone pipeline and gun proposals, campaign staff alerted the White Houses. After Obama last week appeared to deride her proposal for a no-fly zone over Syria, aides called to make sure Clinton understood the criticism wasn’t aimed at her, according to a senior White House official who spoke on condition of anonymity to discuss private conversations.

The White House doesn’t deny that Clinton’s new distance has sometimes created awkwardness for the president.

On immigration, Clinton’s promise to go further than Obama in using executive authority to ease the threat of deportation for immigrants living in the U.S. contradicts Obama’s assertion that he’s done all he can under the law.

Similarly on gun control, just days after Obama said “this is not something I can do by myself,” Clinton seemed to think otherwise. On Monday, she promised to close the “gun-show loophole” through executive action.

White House spokesman Josh Earnest was quickly asked by reporters whether Obama would beat her to it. Earnest said the White House was looking into its options.