President Obama tops Republican Mitt Romney in a head-to-head matchup, according to the latest Fox News poll, which finds American voters feeling more positive about the economy.

Obama would have an advantage of 46 percent to 39 percent over Romney, if the election were held today. Three weeks ago the candidates were tied at 46 percent each.

The national poll, released Wednesday, shows the president's lead is just outside the poll's margin of sampling error.

Click for the full poll results

About a third of voters say they are “extremely” interested in the election. Among just that group, Romney tops Obama by 50 percent to 44 percent.

Overall, each candidate's party support is strong: Most Democrats back Obama (88 percent) and most Republicans support Romney (84 percent).

Among independents, 34 percent back Romney, 29 percent support Obama and more than a third are undecided or say they won't vote (36 percent). Last month, independents broke for Romney by 46 percent to 33 percent.

The gender gap is alive and well, as women continue to be more likely to back Obama (55 percent to 33 percent), while men are more inclined to support Romney (46 to 37 percent).

In general, a 60-percent majority is satisfied with their candidate choices. One voter in three disagrees and thinks “none of the above” should be an option on the November ballot.

Obama voters (74 percent) are much more likely than Romney voters (59 percent) to say they are satisfied with the candidate choices.

Each candidate's backers were asked to say in their own words the main reason they were supporting him. For Obama, the top responses are, he's doing a good job (25 percent), his issue positions (13 percent) and he's a Democrat (11 percent).

Another 11 percent say, “he's not Romney.” Nearly four times as many Romney backers say “he's not Obama” is their top reason (43 percent).

Others are supporting Romney because he's a Republican (14 percent), his issue positions (10 percent) and the economy (8 percent).

Romney supporters are as likely to cite his business background as the issue of same-sex marriage as the main reason for their vote (5 percent each).

Currently 49 percent of voters approve and 47 percent disapprove of Obama's job performance. That's up from 45 percent approval and 51 percent disapproval three weeks ago. In addition, this is his highest approval rating since May 2011, after the raid that killed Usama bin Laden, when some 55 percent approved and 41 percent disapproved.

To Obama's advantage, voters feel the economy is improving. The number saying the economy is in “poor” condition has dropped 14 percentage points from a year ago. And while few voters, 11 percent, rate the economy positively -- that's the highest number since April 2009.

Meanwhile, even though more voters continue to say the economy is in worse shape today compared to four years ago, the number saying it's in better shape is up 11 points (from 17 percent last May to 28 percent today).

The same shift is seen when voters are asked about jobs. Compared to four years ago, 24 percent think the job situation in their area is better today, 41 percent say worse and 32 percent say it's unchanged. A year ago, 13 percent said the job situation was better, 57 percent said worse and 29 percent unchanged (May 2011).

On their family's financial situation, voters are more likely to say they are worse off as opposed to better off today compared to four years ago by an 8-percentage-point margin (23 percent better, 31 percent worse). That's down from a 17-point margin last year (19 percent better, 36 percent worse).

Obama's best marks are on his handling of Afghanistan: 53 percent approve. His lowest approval is 36 percent for handling the federal deficit. Forty-three percent approve of the job Obama's doing on the economy, up from 39 percent a year ago.

What's the “best thing” Obama has done to help the economy? Fifteen percent say he slowed or stopped job loss and the recession, 8 percent cite loans to the auto industry and 7 percent point to the stimulus. The most common response was Obama did “nothing” to help (43 percent).

By a 13-percentage-point margin, voters would pick Romney over Obama to manage their personal money (47 percent to 34 percent). The former governor also comes out on top as the better business partner (48 to 39 percent). Voters think Romney would do a better job creating jobs by a slim 2-point margin (43 to 41 percent).

If hiring a life coach, Obama is the preferred choice by a wide margin, 47 percent to 33 percent. In addition, voters prefer Obama to pick the next Supreme Court justice (46 to 38 percent).

Would Romney have made the same decision Obama made to get Al Qaeda leader Usama bin Laden? By a wide margin of 62 to 24 percent, voters say yes, if Romney were president a year ago, he would have given the order to get bin Laden.

Finally, if Obama were re-elected, 45 percent of voters say they would feel the “country's improving” and would “look forward” to another four years, while a roughly equal number (43 percent) say they would feel the country is “going down the drain” and would “dread” a second Obama term.

The Fox News poll is based on landline and cell phone interviews with 913 randomly-chosen registered voters nationwide and is conducted under the joint direction of Anderson Robbins Research (D) and Shaw & Company Research (R) from May 13 to May 15. For the total sample, it has a margin of sampling error of plus or minus three percentage points.