Top House Democrats are hosting a duo of fundraisers for vulnerable members in their caucus, stoking speculation about their future ambitions.

Maryland Rep. Chris Van Hollen is scheduled to host a fundraiser on Wednesday for Democratic Reps. Ron Barber of Arizona, Ami Bera of California, Joe Garcia of Florida and Ann McLane Kuster of New Hampshire, according to an invitation obtained by CQ Roll Call.

Last week, Democratic National Chairwoman Debbie Wasserman Schultz of Florida and Rep. Joseph Crowley of New York co-hosted a fundraiser for vulnerable House Democrats as well.

“For members with ambition to move up in the leadership, it is a common practice to help your endangered colleagues with their re-election and to help those non-incumbents who have a good chance of winning,” Democratic fundraiser Michael Fraoili noted to CQ Roll Call.

“Help with fundraising is most always welcomed,” he added.

Sources from all three members’ camps brushed off such speculation.

A Van Hollen operative described it as part of his ongoing interest as a former Democratic Congressional Campaign Committee chairman to help freshman and recruits succeed, adding that the fundraiser has been on the books for awhile.  Although Van Hollen is the ranking Democrat on the House Budget Committee, he still keeps an eye on House race politics.

A source close to Crowley similarly described his interest in fundraising as part of his leadership responsibilities with the DCCC. As for Wasserman’s Schultz’s camp, an aide wrote via email that “these events are all about building relationships and helping to make sure that these Members will be successful and part of a future Democratic majority.”

Donations to attend the Maryland Democrat’s reception range from $125 to $10,000 to the Van Hollen Victory Fund. All four of the incumbents’ races are rated Tossup through Lean Democrat by Rothenberg Political Report/Roll Call.