The Battle for America 2010: What Are GOP Prospects for a Senate Takeover One Week Out?

Pretty much every serious analyst is now projecting that the Republicans will take control of the House, gaining more than the 39 seats they need to win. The forecasts from Larry Sabato, Stuart Rothenberg, Charles Cook, Nate Silver, Jay Cost, and the average show a range between a 45- and a 61-seat net gain for the GOP. The numbers have been rising as Election Day nears.

But the battle for control of the Senate is a different story, with many close races and greater uncertainty today than was the case a few weeks back.

If the Republican candidates lose every close race, they would pick up only four net Senate seats to get to 45 total seats. If they have a very good day, and run the table in all the closely contested seats, they could gain as many as 11 to get to 52.

Here is my assessment on where the close races now stand.

GOP held seats

The GOP candidates hold solid leads in all of the open seats to replace GOP senators -- Ohio, Missouri, New Hampshire, Kansas, Florida, and Kentucky -- and in the two contested incumbent seats in North Carolina and Louisiana. The Ohio race is now a blowout for Rob Portman, which may help the GOP in many of the state’s hard-fought House races.

The Kentucky race between Republican Rand Paul and Democrat Jack Conway appeared to tighten a week back, but a Conway ad attacking Paul for some alleged college misbehavior has backfired on the Democrat. That said, while Kentucky has given big wins to GOP candidates for president in the last three elections, races for senator have been regularly very close. Paul should win, but this race will likely remain closer than the others listed above.

Certain GOP pickups

The Democrats have all but conceded that they will lose the open seat races in North Dakota (a 30-point lead for Governor John Hoeven) and Indiana (a near 20-point lead for former Senator Dan Coats), and that Congressman John Boozman will win easily against Democrat Senator Blanche Lincoln in Arkansas.

GOP leads

Since he won the Republican nomination, Ron Johnson has maintained a six- or seven-point lead over Wisconsin Senator Russ Feingold. One poll last week showed Johnson’s lead at only 2 %, but no other survey has confirmed that the race is that close. It is very rare for a candidate to win after being down six or seven points in the polls this late in the race.

In Pennsylvania, until last week, former Republican Congressman Pat Toomey held a similar sized lead over Democrat Congressman Joe Sestak for Arlen Specter’s open seat. A few new polls showed the race was a tie, or even put Sestak ahead by a small margin. However, that “trend” seems to have reversed (there was a burst of new ads for Toomey blasting Sestak last weekend), and Toomey seems to have regained control of the race (he has moved from a three-point deficit to a five-point lead in the Morning Call daily tracking poll). He has a  narrower lead than Johnson holds in Wisconsin, but this race is leaning to Toomey.

Tossups leaning to the GOP

In two of the four pure tossup races, GOP candidates seem to have solidified their position in the last week. Illinois GOP Congressman Mark Kirk has been ahead in the last four surveys, by 2 to 4%, and now seems to have opened up a bit of daylight on Democrat Alexi Giannoulias. Illinois is a very solid blue state, though the GOP seems poised to have its best year since 1998.  Each side has run mostly negative ads against the other candidate, perhaps a partial explanation for why there are still a healthy number of undecided voters, or voters leaning to third party candidates. A "none of the above" option (which is on the ballot in Nevada)  might win 5% in Illinois this year. Nate Silver rates Kirk as just shy of a 2 to 1 favorite, which sounds about right.

In Nevada, GOP candidate Sharron Angle has held small leads (two to three points) in the last few public polls, and was generally considered to have won the only debate she had with Senator Harry Reid. Early voting numbers have been favorable to the GOP in Nevada (as in many other states), though this race is still very close, and a higher than expected Hispanic turnout could lift Reid to victory. Reid has been damaged by Nevada’s high unemployment rate and the unpopularity of the health care reform bill he championed .