A Rocky Second Term for Obama?

Immigration and budget are next battles, but now terrorism is on the radar too.

President Barack Obama talks with staff at Massachusetts General Hospital in Boston on April 18, 2013. The President visited the hospital to meet with patients who were wounded in the bombings at the Boston Marathon following an interfaith prayer service at the Cathedral of the Holy Cross.

The defeat of President Barack Obama's gun-control initiative in the Senate signals he will have more trouble getting his way with Congress than his advisers had expected only a few weeks ago.

Because of the extraordinary polarization that remains in Washington, Obama's goal of bridging the divide will be just as difficult to achieve as ever.

[LIVE BLOG:Manhunt on for Second Boston Bombing Suspect]

And the bombing in Boston has placed terrorism back on the national agenda after a long period when the issue was relatively dormant, potentially pushing other issues out of the spotlight.

All in all, Obama's political position seems surprisingly weak today even though he won a strong re-election victory less than six months ago.

Obama tried to console and inspire the people of Boston Thursday with a well-received speech at an interfaith religious service there. But even his ability to serve as a comforter in chief will have limited effect in helping him win congressional approval of his second-term priorities. These include overhauling immigration laws, finding a "grand bargain" to reduce the deficit and limiting climate change.

[READ: 1 Boston Bombing Suspect Dead]

The tragedy in Boston "certainly puts the president back in the spotlight," says Rutgers political scientist Ross Baker. "One of the most important roles a president has is as national mourner. He is the person who gives voice to our sadness as a national grief therapist." But Baker adds, "It doesn't convert easily to support for his legislative programs."

One problem for the administration is Obama's favorability ratings are slipping, making it tougher for him to persuade legislators to follow his lead and adopt his priorities. About 50 percent of voters say he is doing a good job, down a few percentage points from last November, according to various polls. An AP/GIK survey found only 46 percent of Americans approve of his handling of the economy (down from 48 percent in September), while 52 percent disapprove, up from 48 percent in September.

A bad omen for Obama was the Senate defeat Wednesday of key provisions of a gun control bill he strongly supported. Among those provisions were more background checks for would-be gun purchasers, a ban on the purchase of military-style assault weapons and limits on large magazines of ammunition.

[READ: Boston Bombing Could Reset National Debate]

In addition, Obama's battle with congressional Republicans over budget priorities shows no sign of ending. Obama favors a mix of tax increases and relatively modest spending cuts; the GOP prefers more severe spending cuts and no tax increases.

Beyond the budget, key senators are preparing to push a measure to overhaul immigration laws, another major Obama priority. There appears to be substantial support in Congress for a comprehensive bill that includes a pathway to citizenship or legal residency for those who came to the United States illegally. GOP legislators who had opposed such a bill in the past are reconsidering because passing the legislation is considered a way to limit the erosion of Latino support for the Republican Party.

But the legislation's prospects are uncertain, partly because anything that smacks of amnesty for workers who entered the United States illegally is still a non-starter for many conservatives. And the House, controlled by Republicans, could be the biggest stumbling block of all.

Baker doubts any Obama "charm offensive," such as his recent dining and schmoozing with congressional conservatives, will do much good in moving his agenda. "There is only so much leeway that these members of Congress have," the political scientist says. "You could love the guy but that doesn't mean you can give him what he wants" in legislation.

One way for Obama to retain influence, Democratic advisers say, is to continue using executive orders and unilateral actions to bypass Congress. Obama says he prefers getting congressional approval for his proposals but he will resort to unilateral action if Congress remains balky.

Ken Walsh covers the White House and politics for U.S. News. He writes the daily blog, "Ken Walsh's Washington," for usnews.com and "The Presidency" column for U.S. News Weekly. He is the author of the new book, Prisoners of the White House: The Isolation of America's Presidents and the Crisis of Leadership. He can be reached at kwalsh@usnews.com, and followed on Facebook and Twitter.