Updated

With at least seven or eight of the 37 Senate races in next month's midterm elections considered too close to call, President Obama is headed west to try make a difference in several of them, and help keep the Democrats in the majority. With campaign stops in Washington State, California and Nevada, Mr. Obama will raise money and, he hopes, enthusiasm for Democratic senatorial incumbents. But some Republicans say the administration's western push and emphasis on the Senate suggest it may be conceding the House. "The new firewall is to go out and defend a lot of these seats, senate seats out west when at the beginning of the cycle they thought they were in a much better position," said Kevin Madden, a Republican strategist.

"We're not talking in terms of a firewall, but those are very important races," says White House Senior Advisor David Axelrod, who in a briefing with reporters Tuesday, argued there is no concession, noting the cost of a presidential event is usually prohibitive for a single House race. Nonetheless as polls suggest Republicans are far enough ahead that they are likely to win the races needed to take control of the House, the president appears to be concentrating his efforts on retaining control of Senate.

In this year of the anti-incumbent, polls suggest Republicans have a two to one edge in Senate races considered safe for them or likely to go their way. But they need to virtually sweep the seven or eight tossup races to seize control of the Senate, and the Democrats only need a couple to keep themselves in power.

At a fundraiser Monday night for the Democratic Senatorial Campaign Committee, the president emphasized just how high the the stakes are in this election, saying, "Everything that I've been able to accomplish over the last couple of years has been because I had these great partners."

And Mr. Obama's press secretary made it clear the president wants to keep those partners, and therefore needs to motivate the base. "We are at a point in the election where we normally get to in every election, where -- where individuals are talking to their voters and trying to get them fired up and trying to get them out," said Robert Gibbs.

The president's message - "reminding voters what's at stake, who has their best interests in mind, the steps that have been taken to get us out of the economic hole that we found ourselves in, and to continue to move forward on -- on those policy decisions," said Gibbs. "That's, I think, been the basis for what he's talked to voters about over the past couple of weeks, and I expect that that will continue tomorrow and throughout the trip out west."

In Seattle, the President will raise money for three-term incumbent Patty Murray, who is in a tight race with challenger Dino Rossi. Rossi's strong among Tea Party supporters in Eastern Washington, but the Tea Party's weak in the voter rich area around Puget Sound. And perhaps as important as the money the President raises will be the get out the vote efforts with a rally on Thursday, and a backyard message event with Washington women votes. Rossi doesn't poll well with women so the intent with the backyard event is to highlight democratic legislative achievements that effect women. It's a message Axelrod argues will help not just Murray, but "resonate across the country."

A recent poll by the National Republican Senatorial Committee indicates both Murray and Rossi are seen negatively by almost as many voters as see them in a positive light; Murray by equal 46% shares, while Rossi was seen favorably by 47% and unfavorably by 44%.

Democrats have pulled out all the stops for Murray; Bill Clinton campaigned for her last week, First Lady Michelle Obama will be there in the coming days, and Vice President Biden was out for her Tuesday predicting victory for Murray and the democrats as a whole, "The reports of the demise of the democratic party are premature, we are going to do just fine. I'm here to tell you that on November 3rd, Patty Murray will be leading the senate majority conference as secretary. She will, they will be in the majority again."

In California, President Obama will headline two campaign stops for three term Senator Barbara Boxer, who is pulling ahead of her Republican challenger, Carly Fiorina, in recent polls. A new Fox News - Opinion Dynamics poll gives Boxer a four point lead, but Boxer's substantial cash advantage over Fiorina has been reduced by a nearly $5 million contribution to the challenger from the National Republican Senatorial Committee. And the Chamber of Commerce has spent several million more criticizing Boxer's record. Still, experts question whether Fiorina will have enough money left for an effective get out the vote effort.

Recent polls give Boxer a nearly 20 point lead over Fiorina among Hispanic voters, though Fiorina blames Boxer for voting against a comprehensive immigration reform bill. Boxer accuses Fiorina of supporting Arizona's strict immigration law, now blocked by the courts and highly unpopular among Hispanics.

Business experts give Fiorina high marks for making Hewlett-Packard a more profitable company during her tenure as CEO from 1999 to 2005. But a Boxer ad notes Fiorina was fired from the post, and accuses her of outsourcing 30 thousand jobs, a hugely unpopular move in a state with 12.4% unemployment.

President Obama will also stop in Las Vegas, to try and help embattled Senate Majority Leader Harry Reid hold off a challenge from Tea Party favorite Sharron Angle. Mr. Obama's popularity among Hispanic voters will help Reid, in a state where a quarter of the voters are Hispanic. But a group called Latinos for Reform, headed by a former official for the Republican National Committee, is calling on hispanics not to vote in the election.

But while the president and vice president are going to personally try to save the embattled Senate Majority Leader, Madden argues the outcome won't really be about them. "The Nevada race is going to simply come down to the fact whether those voters like or dislike Harry Reid."

Fox's Wendell Goler and Mike Emanuel contributed to this reoport.