The overarching story in the 2014 Senate fight has been that Republicans were slightly favored to win a majority because they have more paths than Democrats to that majority. That remains true. The FiveThirtyEight Senate forecast has Republicans with about a 57 percent chance of taking control of chamber.
(A quick note: This calculation doesn’t account for Thursday afternoon’s ruling by the Kansas Supreme Court, which took Democrat Chad Taylor off the ballot.)
Over the past 48 hours, new polls have indicated that Republicans are very much alive in Colorado and Iowa. President Obama won both states in 2012, and they haven’t generally been part of what’s thought to be the easiest path to a GOP majority in 2014 (that path is picking up Alaska, Arkansas, Louisiana, Montana, South Dakota and West Virginia while holding on to Kansas).
After two polls in Colorado on Wednesday indicated a 1 or 2 percentage-point race in either direction, a Quinnipiac University survey Thursday gave Republican Cory Gardner a 48 percent to 40 percent advantage over Democratic Sen. Mark Udall. That’s by far the most optimistic result for Republicans in the Centennial State this year.
And in Iowa, a Quinnipiac poll found Republican Joni Ernst up 50 percent to 44 percent over Democrat Bruce Braley early Wednesday. But a Fox News poll that night had the candidates tied at 41 percent. Of the past eight polls in the race, three have had Braley up, two have had Ernst up and three have had a tie.
The result of all the polls taken this year is that FiveThirtyEight has the two states pretty much even. The Democratic candidate is projected to have a 52 percent chance of winning in Colorado and 51 percent chance of winning in Iowa. So, why are the races so tight? One reason is President Obama’s approval in both places. It’s generally low everywhere, but polling has found that Obama is slightly more unpopular in both states than he is nationally. For example, according to Gallup, Obama’s average approval in the first half of the year was 43 percent. In Colorado, his average approval was 41 percent. In Iowa, it was just 38 percent. That’s a change from two years ago, when Obama ran slightly ahead in these states of where he did nationally.
That said, we should be wary of these latest Quinnipiac surveys. Not only are the results the most Republican-friendly of the year in either state, but Quinnipiac’s polls have previously been too pro-Republican at this point in midterm elections. Its likely voter polls in 2010 had Republican Linda McMahon only down 3 percentage points in the Connecticut Senate race; she lost by 12 points. Quinnipiac had Democrat Andrew Cuomo up by just 6 points in the New York gubernatorial race; he won by 29 points. It had Republican John Kasich up by 17 points in the Ohio gubernatorial race; he won by just 2 points.
It’s best to rely on an aggregate of all polls. That won’t be a perfect indicator, but it’s generally better than focusing on the outliers.
CORRECTION (Sept. 19, 3:53 p.m.): A previous version of this article incorrectly referred to a Connecticut poll, listing the poll’s margin in favor of the Republican instead of the Democrat. We’ve included a different survey to better reflect the argument.