New polls narrow the list of Senate battlegrounds

After months of very few reliable polls in this fall’s key elections, new numbers have started to pop up with regularity, giving a better sense of which races are truly competitive as Democrats try to hold off the prospect of Republican control of the Senate.

Kentucky? Probably not. New Hampshire? Less likely.

But Alaska, Arkansas, Iowa, North Carolina: Those four contests remains true tossups. Republicans, who need a net gain of six seats to take control of the Senate, probably have to win in at least two of those states although some other routes to a majority exist.

Republicans seem all but certain to pick up seats in West Virginia, South Dakota and Montana that are currently held by Democrats. In Louisiana, incumbent Sen. Mary Landrieu has consistently trailed her chief Republican opponent, Rep. Bill Cassidy, albeit by small margins.

The latest polls, using a variety of different methods and with different margins of error, include a multi-state round that YouGov, the Internet polling outfit, did for CBS and the New York Times and surveys in several closely contested states released Sunday by Marist for NBC News.

Overall, the polls reinforce the message that Republicans have an edge this year, a product of contested Senate elections taking place mostly in conservative states, a president with mediocre approval ratings and the tendency in most recent midterm elections for Democratic turnout to fall.

But the GOP edge remains relatively small -- leaving the ultimate outcome in doubt.

Of the four closest tossup races, the recent polls indicate that in Arkansas, Republican Rep. Tom Cotton has a small advantage over Democratic Sen. Mark Pryor among those voters who seem most likely to cast ballots in November. The race looks notably different among all registered voters, with some polls showing Pryor in the lead among that larger group. That gap underscores the challenge Democrats face in getting potential supporters to show up at the polls.

In North Carolina, recent surveys all show an extremely tight race, with some giving a small edge to incumbent Sen. Kay Hagan (D) over her Republican opponent, Thom Tillis, the speaker of the state House. On Monday, Public Opinion Strategies, a well-respected Republican pollster, released a survey showing the race tied. That’s not a good sign for Tillis since partisan pollsters generally release the surveys that are most optimistic for their side.

In Iowa, the latest poll, from Loras College in Dubuque, showed Democrat Bruce Braley with a 45%-41% lead over Republican Joni Ernst. That’s consistent with other recent surveys, including the YouGov poll, showing Braley clinging to a small lead despite campaign errors that have drawn criticism from many Democratic operatives.

The biggest uncertainty is in Alaska, in part because the state has a history of being difficult to poll and in part because the Republican, Dan Sullivan, just won his party’s primary on Aug. 19 and may still be consolidating support. The YouGov survey showed Sullivan with a 44%-38% lead over incumbent Sen. Mark Begich, but other recent polls have shown Begich with the lead.

Another possible danger zone for Democrats is Michigan, where Democrat Gary Peters and Republican Terry Lynn Land have been stuck in a very close race. Most nonpartisan analysts have predicted Peters will win the contest, but recent polls have shown mixed results.

Less uncertainty surrounds some other heated contests.

In Kentucky, Democrats have tried mightily to unseat Senate Republican leader Mitch McConnell but clearly seem to be falling short. The Marist poll showed McConnell ahead 47%-39%. Six polls of the race since mid-August have all shown McConnell ahead, with leads ranging from 4 to 8 percentage points.

Democrats also seem to be falling short in Georgia’s Senate race, where polling averages give Republican Rep. David Perdue a consistent three-to-four point lead over Democrat Michelle Nunn.

By contrast, Democrats have gotten good news from recent polls in Colorado. The Marist survey gave incumbent Sen. Mark Udall a 48%-42% lead over his Republican challenger, Rep. Cory Gardner. Four other publicly released, non-partisan polls since July have shown Udall ahead, but by narrower margins, generally within the polls’ margins of error.

The recent polling has also bolstered Democratic hopes in New Hampshire. Last month, a survey from WMUR television gained considerable attention when it showed Republican Scott Brown within two points of Democratic Sen. Jeanne Shaheen. That result seems to have been an outlier -- two more recent surveys have shown Shaheen with a six-point lead, including the YouGov survey, which showed her leading 47%-41%.

Even the most recent polls, however, have not yet caught up with the fast-changing Senate race in Kansas, where the Democrat, Chad Taylor, has been trying to get off the ballot to give an independent candidate, Greg Orman, a clear shot at longtime incumbent Republican Sen. Pat Roberts.

Late Monday, a Survey USA poll of the Kansas race showed a dead heat, with Orman getting 37%, Roberts 36% and Taylor 10%. Taylor’s standing probably will drop further as more voters realize he’s no longer running. Kansas has a long history of electing Republicans to the Senate, but how this year’s contest will turn out remains anyone’s guess.

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