As head of his party’s congressional campaign committee, Rep. Chris Van Hollen of Maryland helped elect 34 new Democrats to the 111th Congress. In his new role as an assistant to Speaker Nancy Pelosi , D-Calif., he’s trying to help them keep their jobs in 2010.

To protect the freshman class of 2008 — the fledgling lawmakers who are Pelosi’s “majority enhancers” — Van Hollen has pushed back against liberal demands for showdown votes with partisan themes. Instead, he has urged a tight focus on the health care overhaul and “core economic issues” and argued against moving some controversial measures that face roadblocks in the Senate.

For example, Van Hollen pushed to shelve a plan for using reconciliation to advance a proposed cap-and-trade system for carbon emission allowances, a proposal that is controversial in heavily industrial states. Instead, he has called for fallback energy initiatives if an all-in-one energy bill loses traction. More recently, he suggested that leaders could delay consideration of climate change legislation until next year.

And according to senior Democrats, his was a leading voice in prodding party leaders to let the Senate move first on such contentious measures as the “card check” proposal (HR 1409), which would allow workers to organize a union by sign-up rather than being limited by employers to secret elections. Given the measure’s dim prospects in the Senate, the delay in the House prevented freshman Democrats from having to cast a vote on a politically charged issue,

“We need to focus on the issues that unite us,” Van Hollen, 50, said in an interview last week. “There are times when you have to ask . . . whether we should pull out all the stops to get something done. There is no point, in the early stages of the new session, in going through a big fight in the House, only to lose in the Senate.”

Now in his second term as head of the Democratic Congressional Campaign Committee, Van Hollen has an interest in protecting many of the party’s newest members. He urges colleagues to keep “30” in mind: That’s roughly the number of seats the majority party has historically lost in the first midterm election after it has elected a president.

“If we can hold our own this time around, we’ll be way ahead,” he said. “Defending and supporting these new members is essential.”

The 2008 class comprises the 32 Democrats elected in November and two subsequently added in special elections: Mike Quigley succeeded Rahm Emanuel (2003-09), now President Obama’s chief of staff, in Illinois’ 5th District, and Scott Murphy was sworn in Wednesday to represent New York’s 20th District, the seat previously held by newly appointed Sen. Kirsten Gillibrand . Many of the freshman Democrats represent swing districts that will be top GOP targets in 2010.

As freshmen like Walt Minnick of Idaho and Martin Heinrich of New Mexico have broken with their party on key issues, Van Hollen has sought to represent their positions at leadership meetings.

Not surprisingly, his GOP counterpart — Pete Sessions of Texas, chairman of the National Republican Congressional Committee — is dismissive of Van Hollen’s efforts to protect freshmen.

“What matters is, they support Nancy Pelosi ,” Sessions said. “The Democratic agenda would eliminate tax cuts and create a new tax on electricity with their cap-and-trade plan. That’s not going to make freshmen popular back home.”

Shades of Emanuel

In the new Congress, Van Hollen has assumed a role resembling the one played by Emanuel, who served as Pelosi’s strategic adviser. He remains in frequent contact with Emanuel, his former boss at the DCCC. For his work as Pelosi’s assistant, he commands a half-dozen aides in addition to his political staff at the DCCC. His team in the Speaker’s complex focuses on helping vulnerable junior lawmakers set up offices, move initiatives and build links to businesses and constituent groups.