WASHINGTON A daunting reality looms for President Barack Obama's Democrats ahead of U.S. congressional elections on Tuesday: Voters from the Republican Party are much more fired up.
Reuters/Ipsos polling data shows Republicans are more certain they will vote, and see their ballot as a way to voice disapproval of Obama's handling of the Ebola outbreak and his health insurance reform law.
The expectation of robust Republican turnout is why many forecasters see strong odds that the party will take over the Senate and expand its majority in the House of Representatives.
"It looks good for the Republicans," said Robert Erikson, a political scientist at Columbia University. "The Democrats are at a disadvantage when it comes to turnout."
About 55 percent of Republicans are certain they will vote, compared with 47 percent of Democrats, according to Reuters/Ipsos polling data for an online survey of 1,725 voters conducted Oct. 25-30. The poll had a credibility interval of 4.2 percentage points for Democrats and 4.8 points for Republicans.
While Republican turnout tends to be higher than Democrats', fewer Americans identify as Republicans, which means contests are tightly fought.
Tuesday's elections play to Republican strengths. While most voters are less interested in non-presidential contests, Republicans' older, higher-income voters are more politically engaged.
Also helping to galvanize Republicans is their frustration over six years of Democratic control of the White House. The president's party has lost seats in Congress in nearly every midterm since 1934.
James Campbell, a political scientist at the University at Buffalo, SUNY, said parties have bucked this trend only when their president enjoyed high approval ratings, as with Bill Clinton in 1998 and George W. Bush in 2002.
Obama's approval rating is just 38 percent, according to other Reuters/Ipsos polling data, and he is a lightning rod for Republicans.
"If there's a unifying theme here, it's a lack of confidence in the administration's management," Campbell said.
Fifty-four percent of Republicans polled said Obama's handling of Ebola would be very important for them when they vote, versus 40 percent of Democrats.
Some 63 percent of Republicans are similarly focused on Islamic State, a militant group America is bombing in Iraq and Syria. That's 20 points higher than among Democrats, and a sizable spread also holds regarding Obama's healthcare overhaul.
Still, many political scientists don't see this year's threats and policy debates as the main factor that will drive Republicans to the polls.
"If these issues didn't exist, there would be something else," said Chris Jackson, research director at Ipsos.
Democrats are doing all they can to boost turnout. In Georgia, where Democrat Michelle Nunn and Republican David Perdue are battling for a Senate seat that is being vacated by a retiring Republican, there are signs that churches have boosted early voting by African Americans, said Michael McDonald, a professor at the University of Florida. These voters are overwhelmingly registered as Democrats and are expected to support Nunn.
A voter's party and race can often be gleaned from early ballots. In North Carolina, McDonald said, Democrats appear to be ahead, having submitted 48 percent of ballots, compared with 32 percent by Republicans.
McDonald said Republicans' early voting drive appears to be gaining steam in Iowa, while the two parties looked to be neck and neck in Colorado.
In the end, Democrats face an uphill battle.
"No matter what, we are going to see a bigger share of Republicans show up," said Jackson.
(Additional reporting by Richard Cowan; Editing by Caren Bohan and Douglas Royalty)