Democratic U.S. Sen. Mary Landrieu widened her fundraising lead over her best-financed Republican challenger, U.S. Rep. Bill Cassidy, in the April-June quarter this year, according to information released Wednesday by both campaigns in this fall’s Senate election.

Landrieu, a three-term incumbent, reported raising $2.15 million in the quarter, which would bring her total brought in since her last campaign, in 2008, to $13.5 million. She spent $3.43 million in the period, leaving her with $6.24 million on hand June 30 and available to spend.

Cassidy, a third-term congressman from Baton Rouge, said he took in $1.6 million in the quarter, for a campaign total of $8 million since his last run in 2012. He spent $750,000 from April through June, ending the period with $5.86 million on hand.

The Republicans, who hold a sizable majority in the U.S. House, are striving to capture a majority of the Senate as well in the fall elections, and their chances are considered very good. They need to pick up six current Democratic seats to win control of the Senate, and the seat held by Landrieu — the only Democrat who now holds a statewide elective office in Louisiana — is one of their prime targets.

The third candidate running a significant campaign, Republican Rob Maness, said that he received $576,000 in the April-June period, bringing his total for the campaign to $1.33 million. He reported spending $556,000 in the quarter, leaving him with $314,000 in cash on hand on June 30. Maness is a retired Air Force colonel and former Entergy executive who lives in Mandeville.

Under Louisiana law, all candidates run in the same field Nov. 4. If no candidate captures a majority then, the top two finishers square off Dec. 6.

July 15 is the deadline for federal candidates to file their second-quarter reports with the Federal Election Commission. While U.S. House candidates file electronically by midnight and the reports appear on the FEC website in short order, Senate candidates need only postmark a mailed, hard-copy report by July 15. Landrieu provided a facsimile of her full 973-page report to The Advocate, while Cassidy and Maness provided the summary pages for their reports.

The reports from the candidates include only contributions to their official campaigns. They do not account for the millions spent in the Senate race so far by independent groups advocating for or against one candidate or another.

The FEC keeps track of both, but the quarterly filings concern the official candidate activity only.

Follow Gregory Roberts of The Advocate Washington bureau on Twitter @GregRobertsDC