U.S. Sen. Amy Klobuchar still doesn't have Republican opponent for her 2012 re-election bid. But whoever emerges starts out nearly $2.5 million in the hole. That's how much the first-term Minnesota Democrat has in campaign cash, according to her most recent filings with the Federal Election Commission. More than $1 million of that was stockpiled in the first three months of this year, a haul that puts her in line with most of the other Democratic incumbents in battleground states. Democrats, who control 53 seats in the Senate, will be defending 23 seats next year. Klobuchar started the year with $1.6 million, and reported a little over $1 million in net receipts between January and the end of March. Some $643,848 came from individuals; another $276,800 came from political action committees. After expenses, she came out of the first quarter of the year with $2,497,871.