– Led by former Minnesota U.S. Sens. Norm Coleman and Rudy Boschwitz, a dozen past and present Republican senators hosted a fundraiser Wednesday for Mike McFadden, one of Sen. Al Franken's leading GOP challengers.

Held at the National Republican Senatorial Committee's Capitol Hill headquarters, the private fundraiser may be the clearest indication yet that McFadden, a former investment banker, has piqued the interest of the GOP establishment in D.C.

"Republicans are impressed with his fundraising and the fact that he is the only candidate to put together a campaign worthy of a statewide race," said Jennifer Duffy, who analyzes Senate races for the nonpartisan Cook Political Report. "It also doesn't hurt that McFadden is an outsider with no voting record."

But in turning to McFadden, national Republicans may be pinning their hopes on a candidate who has yet to firm up support on his home turf.

At least three other Republicans, state Sen. Julianne Ortman of Chanhassen, state Rep. Jim Abeler of Anoka and St. Louis County Commissioner Chris Dahlberg, are considered viable candidates to capture the party's nomination.

McFadden finished second to Ortman in the state straw poll last month and his GOP opponents and Democrats alike have hammered him for not participating in public debates and not fleshing out his stances on a number of issues.

Last week a KSTP/SurveyUSA poll found Franken leading both Ortman and Dahlberg by 8 percentage points. The survey showed McFadden trailing Franken by 10 percentage points.

But with a margin of error of plus or minus 4.3 percentage points, the SurveyUSA poll does not indicate that any candidate is " 'doing better' against" Franken in a head-to-head comparison, Duffy said.

So far, neither public polls nor straw polls have altered the McFadden campaign's post-primary focus. He is widely expected to run in the August primary, whether or not he is endorsed by his party at its May state convention. His campaign staff has repeatedly said he is running against Franken, not the Republican field.

Focus on Franken

With Franken rated as one of the Congress' most liberal lawmakers, his seat has long been a target for Republicans angling to recapture control of the Senate.

But Franken is primed to defend his seat. He has $4.8 million in campaign cash banked and his in-state approval ratings are at an all-time high. Several political handicapping services, including the Cook Political Report, consider him a safe bet to hold on to the seat he won in 2009 by less than a 10th of a percentage point.

McFadden is Franken's closest competitor in the money race; he had $1.7 million cash-on-hand at the end of January. Events like the NRSC, where tickets topped out at $1,000, are adding to that haul and increasing his fundraising advantage over other Republicans in the race.

The NRSC will not endorse a Senate candidate in the Minnesota Senate race ahead of the state primary. But the committee's chairman and vice chairman — along with Senate Minority Leader Mitch McConnell — signed on as hosts for McFadden's fundraiser.

The organization has also met with Ortman, said NRSC press secretary Brook Hougesen.

"We believe the primary is best decided by Minnesotans," Hougesen said. "We've made it a policy to meet with any Republican candidate that asks and offer NRSC resources to any and all who requests them — including using our building as a fundraising venue."

The Minnesota Republican Party has also opted to remain neutral in the race. Party leaders did not respond to a request for comment.

Hougesen said the Republicans' goal remains unseating Franken.

"The NRSC's job is to win elections and they want to help campaigns that they believe are going to be successful," said McFadden's campaign manager, Brad Herold.