Barack Obama's campaign said on Tuesday it hauled approximately $52 million in June. The amount raised by Obama is more than double the amount gathered by John McCain, his main rival in the race for the White House.

On the background of a big haul of cash, Obama’s campaign has been investing in the states with a Republican tradition. Obama’s campaign hauled a total of $72 million so far, campaign officials said Thursday. The amount represents the money his campaign has to spend. Adding the $20 million that the Democratic National Committee had on hand, Obama had $92 million in cash entering this month.

Obama invested $60,000 in Alaska; $3.5 million in Florida; $1.3 million in Georgia; $1 million in Indiana; $100,000 in Montana; $1 million in North Carolina; and $1.8 million in Virginia, the TNS/Campaign Media Analysis Group reported.

"Obama's targeting of these red states is unprecedented. He is clearly looking to expand the playing field,” said Evan Tracey, chief operating officer of CMAG.

The cash gathered in June was more than double than the amount collected in May - $22 million. The big difference can be easily explained through the fact the Illinois Senator was engaged in a tough primary clash with Sen. Hillary Clinton for the Democratic presidential nomination.

John McCain gathered about $27 million cash in June, but combined with the Republican National Committee's bank balance of $68 million, the Arizona Senator had about $95 million to spend at the beginning of the month.

However, Obama Campaign Manager David Plouffe recognized the deficit and wrote in an e-mail to supporters that "McCain and the RNC together still have a huge cash advantage, and we need your help to close the gap."

Obama’s June haul is second only to his $55.4 million raised in February. The amount made him the first presidential candidate to raise more than $300 million.