PLEASANTON, Calif. (KCBS) _ Many politicians are spending Labor Day on the campaign trail, as it usually marks the traditional start of the fall general election campaign.

Political experts are expecting major losses for Democrats in the midterm elections, but most believe only one House Democrat in California is at risk of losing a congressional seat.

Jerry McNerney was reelected in the Obama victory wave in 2008, but things have changed.

University of Pacific political science professor Bob Benedetti said the energy of both the Democratic and Republican parties is different from two years ago.

“The district is pretty much the same, but the energy level isn’t there for the Democrats to mobilize what they would need to do,” said Benedetti. “It’s a district that’s very closely divided.”

He said part of the Republican energy is coming from the National Congressional Committee, which is calling McNerney’s challenger, lawyer David Harmer one of its young guns.

Harmer is running on the platform being used across the country, pledging to reign in federal spending.

President Obama was in Wisconsin on Monday, campaigning for Democrats in what is expected to be a pair of tight races for senate and governor in the state.

“As we’ve heard a lot this year, Republicans are really energized,” said Charles Franklin, a political science professor at the University of Wisconsin at Madison. “So Democrats need every little bit of help they can get.”

President Obama also rolled out a long-term jobs program on Monday that would exceed $50 billion to rebuild roads, railways and runways.