Mediaboss Marketing

(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.

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

Read more:
Poll: Democrats competitive in key southern showdowns