(CNN) - Rep. Joe Sestak's re-election campaign reports Monday that the Pennsylvania Democrat raised more than $1 million in this year's second quarter, with around $4.2 million in the bank.
The two-term congressman from Pennsylvania's 7th District has said that he will challenge Sen. Arlen Specter for the Democratic Senate nomination next year. Specter, a long time Republican, switched his party registration to Democrat earlier this year and has the backing of President Barack Obama and party leaders, as he gears up for re-election in 2010.
Sestak is in the middle of a tour of Pennsylvania's 67 counties, and could have an official announcement regarding a Senate bid when that tour is over at the end of the month.
"We believe this means we will have more cash on hand than any Senate challenger. As you know, this was achieved without the institutional support of the Democratic establishment," says Sestak spokesman Joe Langdon.
Specter's campaign has not released their second quarter figures yet. At the end of the first quarter, Specter had more than $6.7 million in the bank.
Earlier Monday Pennsylvania Republican Pat Toomey said his campaign for the Senate has raked in $1.6 million since he jumped into the race on April 15. Toomey's campaign also announced that they have $1.1 million cash on hand.