By Eric Johnson

CHICAGO, Jan 14 (Reuters) – President Barack Obama’s re-election campaign and its key supporters are looking to grow on a national scale a fundraising concept that was successful in its Democratic stronghold of Chicago, sources familiar with the program said on Saturday.

Eager to widen its donor base, the Obama campaign is using its team of top fundraisers and donors to distribute marketing materials to thousands of potential top-dollar donors across the nation. Those among them who donate $5,000 — the maximum legal contribution to a presidential candidate in the 2012 cycle — will gain a stream of perks large and small, sources said.

The benefits could include free entry to campaign fundraisers featuring the president, access to strategy sessions at headquarters, and pizza parties at the homes of supporters to watch upcoming voting contests to pick the Republican candidate challenging Obama for the White House in 2012.

The campaign hopes to draw thousands to this category of donor, which so far includes roughly 80 people in Chicago, the Democratic bastion where Obama has supporters with deep pockets.

Members of the pilot group, called the “Chicago Leadership Circle,” paid $5,000 either in a lump sum or over five months to get “unparalleled networking opportunities” to meet with campaign officials and key political operatives coming to Chicago for events and strategy meetings, according to sources and the program’s marketing materials.