Republicans hold a narrow, but steady, lead in the contest for control of the Senate, according to polls released Sunday.
Enough races remain extremely close that Democrats could still keep control of the chamber, but only if all the breaks go their way. So far, that's not happening in the campaign's closing weeks.
Democrats appear to have lost ground in extremely close races in Iowa and Colorado, although they have gained ground in Georgia. In Kansas, an embattled Republican incumbent has come back in his fight against an independent who has the backing of many Democrats.
In the Iowa race, Republican Jodie Ernst has a three-point edge over Democrat Bruce Braley, 49% to 46%, according to a new NBC/Marist survey, maintaining the small lead she established in the survey earlier this month. A New York Times/CBS/YouGov survey, also released Sunday, showed the race tied at 44% each.
Both polls showed a virtual tie in Colorado, where Democratic Sen. Mark Udall has slipped in his race against Republican Rep. Cory Gardner. The NBC/Marist poll showed Gardner ahead, 46% to 45%, while the CBS/NYT/YouGov survey showed Udall ahead, 47% to 46%, in both cases well within the polls' margins of error. Udall held a lead in the race earlier this fall, but several polls have shown him slipping.
In Kansas, Democrats have been hoping that Greg Orman, a businessman and political independent, could knock off incumbent Republican Pat Roberts. Orman established a lead in the race earlier this fall after the Democratic candidate dropped out. But Republicans have mounted a major effort to rescue Roberts and have gained ground.
Kansas is a heavily Republican state, and the two polls, along with other recent surveys, indicate that some voters who had previously turned their backs on Roberts have returned to their party loyalty as election day has approached.
The NBC/Marist poll now shows Orman just one point ahead of Roberts, 45% to 44%. The CBS/NYT/YouGov survey shows Roberts up by four points, 42% to 38%, with a large number of voters undecided.
The one bright spot for Democrats is Georgia, where Democrat Michelle Nunn has mounted a strong challenge to Republican David Perdue. Several recent polls have showed Nunn gaining, with some giving her a small lead. The CBS/NYT/YouGov survey shows her still trailing, 47% to 44%. A third-party candidate is also in the race, and under Georgia law, if no candidate hits 50%, a runoff will be held Jan. 4.
In another extremely close race in the southeast, Democratic Sen. Kay Hagan of North Carolina has been clinging to a small lead against her Republican challenger, Thom Tillis, the speaker of the state House. The CBS/NYT/YouGov survey shows Hagan still ahead, 44% to 41%, but the NBC/Marist poll shows the two tied at 43% each.
Republicans need a net gain of six seats to take control of the Senate. At least nine Democratic-held seats are in clear jeopardy.
In addition to the close races in Iowa, Colorado and North Carolina, Republicans have clear leads in recent polls for seats held by Democrats in Montana, West Virginia, South Dakota and Arkansas.
In Louisiana, incumbent Democrat Mary Landrieu is trailing in a multi-candidate race which will almost certainly go to a runoff in December in which the GOP would be favored to win. And in Alaska, Democratic Sen. Mark Begich has trailed in several recent surveys, although the state has a history of confounding pollsters.
Some polls have also shown Republican Scott Brown mounting a strong challenge to incumbent Democratic Sen. Jeanne Shaheen in New Hampshire. The CBS/NYT/YouGov survey, however, shows Shaheen ahead, 46% to 41%.
The Marist poll is a traditional telephone survey while the YouGov poll uses an Internet panel to survey voters in all states with competitive contests. The margins of error for both surveys vary depending on the state.