Poll: Democrats competitive in key southern showdowns

(CNN) - New polls in three southern states with crucial Senate contests this year indicate that Democrats remain very competitive as they try to keep control of the chamber.

But another new survey suggests that Republicans nationwide have a ten point advantage over Democrats when it comes to voter enthusiasm.

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According to NBC News/Marist polls released Monday, the Democratic incumbent in Arkansas currently enjoys a double-digit lead over his GOP challenger, while Democratic candidates in Georgia and Kentucky are tied up with the GOP as they try to turn red seats blue. Those two states are, as of now, the only places where Democrats hope to go on offense in the battle for the Senate.

Overall, the Democrats hold a 55-45 majority in the Senate (including two independents who caucus with the party). But the party's defending 21 of the 36 seats in play this November, with half of those Democratic-held seats in red or purple states.

And one of those states is Arkansas, where two-term Democratic Sen. Mark Pryor faces a difficult re-election this year. But by a 51%-40% margin among registered voters, Pryor leads first-term Rep. Tom Cotton, the all-but-certain Republican challenger. The new survey's in line with a recent New York Times Upshot/Kaiser Family Foundation poll that indicated Pryor with a ten-percentage point lead. Other recent polls also put Pryor ahead of Cotton.

Pryor's 11-point lead comes despite President Barack Obama's poor approval rating in Arkansas (34%) and the unpopularity of the federal health care law. By a more than two-to-one-margin Arkansas voters strongly say the health care law's a bad idea (49%) rather than a good idea (22%).

CNN/ORC Poll: Majority say keep or improve Obamacare

"So far, Senator Pryor has staved off Cotton's challenge," says Dr. Lee M. Miringoff, director of the Marist College Institute for Public Opinion. "Holding this seat is no easy task for a Democrat with President Obama's approval rating at 33% in the state."

The poll indicates Pryor grabbing the support of 32% of those who give Obama a thumbs down. Also helping Pryor: Arkansas voters have a more positive view of the incumbent (50%-35% favorable/unfavorable rating) than Cotton (38%-39%).

Dead heat in Kentucky

According to the poll, the race between Senate GOP Leader Mitch McConnell and Kentucky Secretary of State Alison Lundergan Grimes is all tied up. Forty-six percent of those questioned say they back the five-term McConnell, with 45% saying they support Grimes, the Democratic challenger. The survey is similar to the most recent polls which also indicated a deadlocked race.

Grimes is tied with McConnell even though the President's approval rating stands at just 32%, and by a 43%-27% margin, Kentucky voters strongly say the Affordable Care Act, better known as Obamacare, is a bad idea.

Republicans are trying to tie Grimes to the President. The latest example: the narrator in a new television commercial out Monday from the pro-McConnell outside group Kentuckians for Strong Leadership says "ObamaCare. The War on Coal. That's Obama's agenda. And Alison Grimes supports Obama."

But the poll indicates McConnell's approval (41%-46%) and favorable (42%-46%) ratings slightly underwater with Kentucky voters.

While Grimes faces no serious opposition in Kentucky's May 20 primary, McConnell is fending off a primary challenge from the right from businessman Matt Bevin, who enjoys strong support from many tea party groups and influential conservative organizations. While the race has seen big spending - both by the campaigns and from outside groups - McConnell is expected to cruise to renomination.

And the new poll backs up that assessment: McConnell leads Bevin 57%-25% among those likely to vote in the GOP Senate primary.

All tied up in Georgia

Georgia also holds primaries on May 20, and there's a wide open free-for-all for the seat of retiring GOP Sen. Saxby Chambliss. Republican Reps. Phil Gingrey, Paul Broun and Jack Kingston, former Georgia Secretary of State Karen Handel, and businessman David Perdue are the major GOP candidates in the race for their party's Senate nomination.

According to the poll, the more moderate candidates are ahead of the more conservative candidates in the race. Perdue's at 23% among likely GOP primary voters, with Kingston at 18%, Handel at 14%, and Broun and Gingrey each at 11%. With none of the candidates likely to crack 50%, the race will most likely head to a July runoff between the top two finishers.

The winner will face off in November against Michelle Nunn, the all-but-certain Democratic nominee and daughter of former longtime Sen. Sam Nunn, a household name in Georgia.

The poll indicates Nunn competitive with all of the Republicans: Nunn 41%-Perdue 45%; Nunn 43%-Kingston 43%; Nunn 42%-Handel 39%; Nunn 42%-Broun 43%; Nunn 44%-Gingrey 42%.

President Obama stands at 41%-50% approval/disapproval among Georgia voters.

There's also a high profile gubernatorial race this year in Georgia. The poll indicates first-term GOP Gov. Nathan Deal leading the all-but-certain Democratic challenger, state lawmaker Jason Carter (the grandson of former President Jimmy Carter), 50%-40%.

GOP has the intensity edge

Republicans have a 10-point advantage over Democrats when it comes to enthusiasm, according to a Gallup poll released Monday. Forty-two percent of Republicans and independents who lean towards the GOP say they're more enthusiastic about voting than usual, compared to 32% for Democrats and independents who lean towards the Democratic Party.

Overall, 35% of registered voters nationwide say they're more enthusiastic about voting, with 53% saying they are less excited to cast a ballot than in past elections. That's a dramatic change from the last midterm elections, in 2010, when the numbers were reversed.

Obama: Democrats 'don't vote' in midterms

The poll follows previous surveys this year that indicated Republicans more intense than Democrats about voting. Conventional wisdom dictates that the GOP has an advantage over the Democrats in midterm contests. White voters and older voters, key to the Republican base, tend to cast ballots in bigger percentages in midterms than younger voters and minorities, who are an important part of the Democrats' base.

The Gallup poll was conducted April 24-30, with 1,336 registered voters nationwide questioned by telephone. The survey's overall sampling error is plus or minus three percentage points.

The NBC News/Marist poll in Arkansas was conducted April 30-May 4, with 876 registered voters questioned by telephone. The survey's sampling error is plus or minus 3.3 percentage points.

The NBC News/Marist poll in Georgia was conducted April 30-May 5, with 2,196 registered voters questioned by telephone. The survey's sampling error is plus or minus 2.1 percentage points.

The NBC News/Marist poll in Kentucky was conducted April 30-May 6, with 2,353 registered voters questioned by telephone. The survey's sampling error is plus or minus two percentage points.