Democratic U.S. Sen. Amy Klobuchar started the election year with $4.6 million in the bank.
She also said she raised $1 million in the last three month of 2011. Federal campaign finance reports were due Tuesday.
Those figures, plus her polling numbers that place her in the top ten of most popular Senators, will do little to encourage more potential challengers to come forward.
Three Republicans have taken on the challenge. None has raised anything close to Klobuchar's haul.
Former state Rep. Dan Severson, a Republican, said he raised $45,171 between October and the end of December and closed the year with $34,157 on hand. Republican Anthony Hernandez, who also hopes to take Klobuchar, said that he hadn't done any significant fundraisers and said he would report under $10,000 raised in the quarter. Joe Arwood, a third Republican running against Klobuchar, raised $1,170 in the last cycle and has $1,883 cash on hand.