Similarly, in Iowa, the Senate race in 2010 wasn't competitive, unlike the one this year. Four years ago, Sen. Charles Grassley (R) was such a heavy favorite to win re-election that there wasn't much polling of the race, at least not by independent (unaffiliated) outfits. A Des Moines Register poll conducted in late October nailed Grassley's margin of victory over former U.S. Attorney Roxanne Conlin (D): 31 percentage points. This year, the Register's latest poll found state Sen. Joni Ernst (R) ahead of Rep. Bruce Braley (D) by just one percentage point, 47% to 46%. That comports with the current RCP Average of polls, which has Ernst leading Braley by 1.7 percentage points.
Same story in Georgia: The Senate race in 2010 wasn't competitive at all; this year it's a nail-biter. However, there was something unique about the Georgia Senate race four years ago. Sen. Johnny Isakson (R) handily defeated his Democratic challenger, State Labor Commissioner Mike Thurmond, 58% to 39%, but polls overestimated his margin of victory. All the publicly released poll results in late October that year showed Isakson winning by anywhere from 21 to 30 percentage points. This year, the polls are showing a virtual tie between businessman David Perdue (R) and Points of Light CEO Michelle Nunn (D); Perdue's lead over Nunn in the RCP Average today is one-half a percentage point. Because this race will go to a runoff if no candidate wins an outright majority of the vote in the general election, and because all the polls are indicating that is exactly what will happen, further analysis of this race seems premature right now.
Admittedly, the dynamics of an open race are so different from a race with an incumbent in it that trying to use one to predict what will happen in the other may not be empirically sound. So, what races can we look to for an apples-to-apples comparison? Try Arkansas, where Sen. Blanche Lincoln (D) was probably the most vulnerable incumbent in the U.S. Senate in 2010, and she lost in a landslide to then-Congressman John Boozman (R), who won Lincoln's seat with 58% of the vote. (Lincoln received 37%, almost exactly her poll position in the RCP Average--37.8%--on October 26, 2010.) Late deciders must have broken for Boozman, who stood at 54.5% in the RCP average one week out. If history repeats itself this year, then the lone remaining Democrat in Arkansas's congressional delegation, Sen. Mark Pryor (D), will soon be replaced by Rep. Tom Cotton (R), who today leads Prior by five percentage points in the RCP Average, 46.8% to 41.8%.
Colorado was one state where the pollsters really missed the mark in 2010. A week before Election Day that year, Weld County District Attorney Ken Buck (R) led Sen. Michael Bennet (D), who had been appointed to the seat in 2009, by one percentage point in the RCP Average. By Election Day, however, that lead had grown to three percentage points. Buck appeared to have the momentum going into the election, but Bennett managed to pull out one of the tightest victories that year, winning election to a full term by less than 2% of the vote. (Buck received 46.4% of the vote, significantly less than his 49.3% standing in the RCP average on Election Day, while Bennett took 48.08%, slightly more than the 46.3% the RCP average of polls had him winning. What probably happened is that a lot of voters who were going to vote for Buck ended up voting for one of the third-party or "Independent" candidates on the ballot, or maybe they just didn't vote.) This year, Rep. Cory Gardner (R) has a slightly larger lead over incumbent Sen. Mark Udall (D), 3.3 percentage points in the RCP Average, and he hasn't made a lot - or really any - of the stupid mistakes Buck made four years ago. Republicans are also determined this year not to get caught off guard again by the Democrats' ground game. Suppose for a minute, though, that this race plays out from here just like the 2010 contest did. That would mean Gardner would continue to gain in the polls and head into Election Day with a lead of between five and six percentage points in the RCP average. If the actual election results then showed a four-point swing towards Udall, then Gardner would still win. It's also worth noting that Udall is polling much lower than Bennett was four years ago. However, there are also more "undecided" voters than there were at this point in the 2010 race, so while Udall has more ground to make up than Bennett did in the last week of the campaign, there are also more potential late deciders who could swing this race.
What about the "generic ballot"? Republicans have a six-point advantage among likely voters in the Washington Post/ABC News poll out this week. That's even better than they were doing four years ago, writes FOX News digital politics editor Chris Stirewalt:
Double, double, toil and trouble - Struggling with female voters and young voters, Democrats fare worse in the latest WaPo/ABC poll than they did at the same point ahead of the disastrous 2010 election and at the same level as the punishing 1994 midterm elections that cost them both houses of Congress. Without any significant increase in Democratic intensity since the previous polling cycle, the auguries are getting dire for the president’s party.