Several Democrats in competitive Senate elections next year announced solid second-quarter fundraising reports Tuesday.

Sen. Jon Tester (Mont.), Rep. Shelley Berkley (Nev.) and Sen. Bill Nelson (Fla.) said they will report raising more than $1 million on their federal fundraising reports covering April through June, which are due to be postmarked to the Federal Election Commission by midnight Friday. With Senate control hanging in the balance, each is running in a state that will be among the most closely watched.

Sen. Joe Manchin (W.Va.) has a solid war chest, $1.3 million. He, too, should expect a challenging election for a full term, though it’s unclear whether he will encounter a top-tier opponent.

Sen. Debbie Stabenow (Mich.) raised $1.5 million and had $4.1 million in the bank as of June 30, setting her own fundraising record. But no Republican has stepped up to challenge her.

The Democratic Senatorial Campaign Committee touted its candidates’ numbers, as well as those previously announced by Virginia Senate candidate Tim Kaine and Sens. Sherrod Brown (Ohio), Bob Menendez (N.J.) and Bob Casey (Pa.).

Tester, who is facing a challenge from Rep. Denny Rehberg (R-Mont.), is expected to report raising $1.3 million and $2.3 million on hand. Rehberg has not yet announced his fundraising figures. Polls suggest this will be one of the closest races of the 2012 cycle.

In Nevada, Berkley announced raising more than $1.2 million for her campaign against appointed Sen. Dean Heller (R). Berkley had more than $2.5 million in the bank, a strong start for the candidate who may represent the party’s best chance at picking up a Senate seat. Heller raised just over $1 million and had $2.3 million in cash on hand.

The Nelson campaign announced that the two-term Senator raised $1.9 million in the second quarter and had more than $6 million on hand at the end of June.

Five Republicans are vying for the nomination to take on Nelson, and three have released fundraising totals for the second quarter. Former Sen. George LeMieux raised more than $950,000, Florida Senate President Mike Haridopolos pulled in more than $900,000 and former Florida House Majority Leader Adam Hasner posted more than $560,000.

Democrats are defending more than twice as many Senate seats as Republicans are in 2012.

In other Senate fundraising news, National Republican Senatorial Committee Chairman John Cornyn (Texas) announced Tuesday that former Hewlett-Packard CEO Carly Fiorina will serve as NRSC vice chairwoman. Republicans will likely use Fiorina’s connections with wealthy West Coast donors to boost their coffers.

The California businesswoman is no stranger to Senate races. She challenged Sen. Barbara Boxer (D-Calif.) unsuccessfully last year. Sen. John McCain (R-Ariz.) also had Fiorina serve as the Republican Victory chairwoman for his presidential run in 2008.