Topeka ? U.S. Sen. Pat Roberts raised more than twice as much as his primary challenger Milton Wolf during the last three months, according to campaign finance reports released Tuesday.

Roberts, a three-term incumbent Republican, reported taking in $796,588 from April through June, compared with $340,683 for Wolf.

The reports also show Roberts with nearly 10 times as much cash on hand heading into the final weeks of the primary campaign.

The Roberts campaign ended the quarter with just over $2 million in cash on hand, compared with $280,000 for Wolf.

For the entire election cycle, the reports showed, Roberts has received $4.4 million in contributions, compared with about $897,000 for Wolf. Roberts reported spending just over $3 million so far in the campaign, compared with $647,000 by the Wolf campaign.

Tuesday was the deadline for congressional candidates to file quarterly campaign finance reports with the Federal Election Commission.

Wolf has focused his campaign criticizing Roberts as a Washington insider, arguing that Roberts has spent 47 years in Washington and does not really maintain a residence in Kansas.

Roberts, meanwhile, has defended his record and has characterized Wolf as irresponsible, citing news stories from February detailing how Wolf, a Johnson County radiologist, once posted X-ray images of gunshot victims along with inappropriate comments on a Facebook page.

According to a SurveyUSA poll conducted in June, Roberts held a 56-23 percent lead over Wolf among likely GOP primary voters.