Washington ? In a campaign season of anti-establishment ferment, some of the Republican Party’s best-known insiders are building an ambitious fundraising machine for the fall elections and beyond.

They started with a bang in April, cashing a $1 million check from a Texas oil magnate. After a quiet May, friends and foes are watching to see if the new organization’s core group, American Crossroads, can reach its goal of raising $52 million by November.

Karl Rove, who was President George W. Bush’s top political strategist, and Ed Gillespie, a former Republican Party chairman and White House aide, modeled their network on successful operations created by Democrats several years ago.

American Crossroads is a 527 organization — named for a section in the tax law — exempt from limits on campaign fundraising and spending that apply to party-affiliated groups. It can tap rich conservatives, such as Trevor Rees-Jones, president of Dallas-based Chief Oil and Gas, who chipped in the first $1 million. But eyebrows rose in political circles when the group filed its next monthly report with the Internal Revenue Service, showing only $200 raised in May.

Steven Law, a former U.S. Chamber of Commerce lawyer and now president of American Crossroads, said the group has about $30 million in pledges that Rove, Gillespie and others secured during recent trips to various cities.

“We feel very good about the progress we’ve made,” Law said, predicting a strong fundraising report for June.

He said the idea for American Crossroads grew from talks last fall involving Rove, Gillespie and other conservatives who feel liberals outhustled the GOP after the McCain-Feingold campaign finance law in 2002 and subsequent court rulings set new limits — and opportunities — for political activities.

The goal, Law said, is to build “an enduring and robust outside organization that can, in the long run, compete with the very successful groups the Democrats have built.”

Pro-Democratic groups that Law and others cite as role models include Moveon.org, Democracy Alliance — founded by liberal billionaire George Soros — and Democracy Corps, founded by Democratic strategists James Carville and Stanley Greenberg.