Americans' optimism about the economy hasn't changed, but most of them might feel better about who's running it if Republicans were to win both chambers of Congress, according to new data from Gallup.

The U.S. Economic Confidence Index, which measures how Americans feel about the state of the economy today and how they expect it to perform in the future, is holding steady at around -15 after a positive bump from -20 a few weeks ago.

However, most Americans believe Republicans in Congress would do a better job of dealing with the economy than their Democratic counterparts, according to another Gallup poll.

“There is universal agreement across party lines on the importance of the economy this year, and Republicans have a slight perceptual advantage as the party best able to handle the issue,” Gallup researchers wrote. They added that Republicans' advantage on this issue could stem from “the blame the voters may place on the party that currently controls the White House.”

The poll found that American voters trust Republicans more than Democrats in general when it comes to economic issues, such as taxes and the federal deficit, but they trust Democrats more on such issues as health care and inequality.

Of nine possible issues, voters ranked the economy as the most important. Nearly 90 percent said it was “extremely” or “very” important, and 48 percent said that Republicans can do the best job handling it. On the noneconomic front, voters said they feel Republicans are better at handling foreign affairs.

Gallup Voter Priorities
Economic issues topped the list of most concerning issues for American voters, according to a Gallup poll. Gallup / IBTimes

In regard to domestic issues, respondents said they trust Democrats more than Republicans to deal with the Affordable Care Act, immigration, same-sex marriage and global warming, although those issues weren’t ranked as among the most important on the survey.

“Hot-button issues such as immigration and global warming, and issues that have been much in the news recently, such as foreign affairs and immigration, have below-average importance,” the Gallup report said.

Gallup researchers surveyed more than 1,300 registered voters from 50 states, from April 24-30, asking them to rank the importance of certain issues in terms of how they plan to vote for senators and representatives, and which party would do a better job.