With the economic crisis deepening and unemployment rising, attention is turning to the nation’s immigrant workers.

President Obama’s recent stimulus package included a provision in which banks receiving bailout money were limited from hiring foreign workers. Senators Dick Durbin of Illinois and Charles Grassley of Iowa are introducing legislation in Congress that would tighten enforcement in granting H1-B visas for skilled foreign workers.

In the Silicon Valley, this conversation is especially significant.

On one side of the debate, there is the area’s tech industry, which is peopled by large numbers of skilled foreign-born workers in the engineering, research and innovation departments at companies like Google, Yahoo and Hewlett-Packard.

On the other side are labor groups who claim these H-1B visa holders are displacing U.S. workers.

While the recession has spurred a greater tendency towards protectionism, Silicon Valley business leaders maintain that in order to continue the area’s legacy of innovation and progress, increasingly stringent immigration caps must be relaxed.

In 2001, the cap on H-1B visas reached 195,000. Since 2004, the number has decreased to just 65,000, according to a recent New York Times report.

The Silicon Valley Leadership Group has long advocated for raising the cap on H-1B visas. The group, made up of 290 member companies including Apple, Google and Intel, regularly works with local government to improve the economic health and quality of life in the Valley.

The group is headed to Washington next week to speak to members of Congress and the administration about the immigration issue for highly skilled workers, among other topics. The group is not pushing for a defined number of H-1B visas per year, but believes that the cap should fluctuate based on demand.

“It’s a mistake to think there is just a fixed number of jobs. Someone gets a job; someone else doesn’t get a job. That’s true for only an immediate period of time,” says Phil Yost, a spokesman for the group. “When companies get the best people, they grow, they prosper, and the total number of jobs available expands.”

Top Silicon Valley executives including the chiefs of Sunpower, Serious Materials, Wyse Technology and Brocade will lead the two-day trip, which starts on May 4.

Yost says that while the group does not expect much action on the immigration issue this year, they will continue to advocate for elements they believe should be part of national immigration policy.

The group will also speak to federal legislators about other local projects including funding via the Federal Transportation Reauthorization Bill for the BART extension to Silicon Valley and advocating for federal money to support a housing trust in Santa Clara County.

On immigration, in addition to talking about raising the H-1B visa cap, the group will speak about exempting foreign advanced degree graduates from the cap, and increasing the number of green cards granted.