By Roberta Rampton

SEATTLE (Reuters) - The financial and political fallout from Britain's vote to leave the European Union has added to a string of setbacks for President Barack Obama as he works to burnish his legacy before his presidency ends in January 2017.

The Brexit decision came after a deadlock in the U.S. Supreme Court on Thursday effectively ended Obama's push to overhaul immigration rules, and the week after the worst mass shooting in modern U.S. history.

For Obama, the reversals heighten pressure on him and fellow Democrats to work harder for the Nov. 8 elections - particularly for the party's presumptive presidential nominee, Hillary Clinton, who represents his best shot at making sure more of his policies are not rolled back.

Speaking at two fundraising events in Seattle on Friday night, at the end of an arduous day that saw global markets plunge after the Brexit vote, Obama acknowledged the shifting political winds four months from the vote.

"If you didn't think the stakes were high before, you should think the stakes are pretty high right now," Obama said at an intimate fundraising dinner at the home of tech executive Steve Singh. Guests, arranged in two long tables, paid $10,000 to $66,800 per couple.

Obama has argued technology and globalization can increase opportunities for all, but conceded that recent events show many people are frightened by global competition and feel left behind.

Donald Trump, the presumptive Republican presidential nominee and political novice, has tapped into those concerns about the economy, trade and immigration - fears that also figured into the UK campaign to leave the EU.

"Unfortunately, when people are anxious and scared, there are going to be politicians out there who try to prey on that frustration to get themselves headlines and to get themselves votes," Obama told about 3,000 people who paid $250 and up to attend a campaign-style event on Friday for Washington State's Democratic Governor Jay Inslee.

Clinton regained a double-digit lead over Trump this week, according to a Reuters/Ipsos poll released on Friday that showed 46.6 percent of likely American voters supported Clinton while 33.3 percent backed Trump.


In April, Obama had taken the unusual step of traveling to London to help the "Remain" camp of the referendum for his friend and ally, Prime Minister David Cameron, who will now leave office before Obama does.

The financial uncertainty from Brexit threatens to weigh on the strong U.S. economy and undo some of the recovery seen since Obama took office in early 2009 at the height of the financial crisis.

Earlier this week, Obama's plan to remove the specter of deportation for millions of undocumented immigrants was quashed when the Supreme Court deadlocked over lifting a hold on the action.

And two weeks ago, the nation's worst mass shooting in modern history, at a gay nightclub in Orlando, raised questions about how Obama is dealing with home-grown extremism - and served as a reminder of his failure to convince the U.S. Congress to tighten gun laws.

The setbacks show the limits of action that any president can take unilaterally, said Justin Vaughn, a political scientist at Boise State University.

"I don't think Obama's legacy has taken a hit so much as it came back to earth," Vaughn said.

Still, the impression that his administration is unable to control its own political destiny could weigh on how history views Obama's time at the White House, said Brandon Rottinghaus, a political scientist at University of Houston.

"Presidents are often judged by what happens in the ninth inning, so President Obama's last few months in office are important to cementing and enhancing his legacy," Rottinghaus said.

(Additional reporting by Ayesha Rascoe in Washington; Editing by Mary Milliken)