Updated 10:20 a.m. Monday | Ambitious House Democrats looking to position themselves as future caucus leaders thought they’d face stiff competition from Rep. Chris Van Hollen.

But with the Maryland Democrat, Budget Committee ranking member and former two-term Democratic Congressional Campaign Committee chairman now saying he’ll run for Senate, the field has changed.

Sources say Van Hollen wasn’t the presumptive heir to Minority Leader Nancy Pelosi’s mantle, even though the California Democrat has been grooming him over the years, giving him increasing responsibilities and ensuring he always had a seat at the table.

“Conventional wisdom in the caucus always dictated that Van Hollen was Leader Pelosi’s choice to succeed her; he’s a smart, likable guy with serious policy chops and political acumen,” a senior aide to a Democrat with leadership ambitions wrote in an email to CQ Roll Call. “But it never would have been a guarantee.”

Democratic aides emphasized that while Pelosi’s influence now in the caucus shouldn’t be underestimated, her power will begin to dissipate the moment she announces she’s leaving.

But no matter what the future might have held, Van Hollen’s announcement that he will seek to replace retiring Democratic Sen. Barbara A. Mikulski undoubtedly removes one key roadblock for other Democrats looking to move up in the leadership ranks.

Sources stressed that in gaming out what comes next, the first person to account for is Minority Whip Steny H. Hoyer, another Maryland Democrat who has been waiting for years to be party’s No. 1 in the House.

If Pelosi, 74, were to retire, the 75-year-old Hoyer would run to replace her and, barring any unforeseen circumstances, he would win, having amassed tremendous loyalty and respect among the rank and file. This would have been the case no matter what Van Hollen decided; no member serious about being a party leader would challenge Hoyer.

But members wouldn’t expect Hoyer’s reign to last as long as Pelosi’s. With a caucus membership that’s younger and increasingly antsy, Hoyer would be considered a transitional figure between the old and new guards.

Democratic lawmakers, aides and operatives speaking to CQ Roll Call said Hoyer would surround himself with people who could follow in his footsteps, and collaborate with the members who filled in the down-ballot leadership slots of whip and perhaps assistant leader in the event the member currently in that role, 74-year-old James E. Clyburn of South Carolina, retires too.

That’s where the jockeying among members would really start, in the competition for the open positions in a Hoyer leadership regime that could give leadership aspirants a leg up after his departure.

Two members especially benefiting from Van Hollen’s departure are the chairman and vice chairman, respectively, of the House Democratic Caucus: Xavier Becerra of California and Joseph Crowley of New York.

Becerra, who might end up running for the Senate seat to be left empty by retiring Democrat Barbara Boxer, could stay in the House and launch a campaign to be the first Latino to lead the caucus. He’ll be thinking about his future carefully at this point: His final term as caucus chairman is at the end of this Congress, at which point he’ll be a man without a seat at the leadership table.

Pelosi has in the past accommodated other Democrats who have termed out of their leadership responsibilities. Van Hollen, after two terms leading the DCCC, got elevated to ranking member on Budget and was given de facto leadership status; Rep. Steve Israel, D-N.Y., subsequently served two terms as DCCC chairman and was then given an entirely new leadership role heading up the Democratic Policy and Communications Committee.

There’s no telling what Pelosi, if she chooses to stay for another two years after 2016, could or would do to help Becerra, who also has a long way up the seniority ladder for increased power on the influential Ways and Means Committee on which he currently serves and has sought to make a mark.

Unlike Van Hollen, who has been elevated and appointed to his various leadership positions rather than had to run for them, Becerra knows what it takes to run a campaign inside the caucus.

Crowley is in the same camp, but his edge is even greater in that regard: He has run in a contested leadership race — and won. His grit and determination to get any seat at the table would go a long way in ultimately winning a more senior role. He is also something of a favorite in the caucus, extraordinarily personable and well-liked by a varied cross-section of members.

“Running a race is not simplistic. It takes a lot of energy, effort,” said a House Democratic aide. “You have to ask your colleagues for their support. It is totally different than being appointed to chair of DCCC or being the ranker of Budget. It’s just different.”

If Crowley runs against Becerra, the New York Democrat could be hurt by his more moderate record, especially with a left-leaning caucus that sees Becerra as a progressive stalwart. And in a caucus where diversity at the top is crucial, some Democrats might balk at promoting a white Irish-Catholic from Queens.

Then there’s Rep. Debbie Wasserman Schultz of Florida. As head of the Democratic National Committee, she has a tremendous fundraising network; as a woman, she would ensure gender diversity in the ranks wouldn’t go away with Pelosi. She, too, could decide to run for Senate in the event Republican Macro Rubio resigns to run for president. But if she stays in the House, like Becerra, she will have to choose her trajectory wisely.

Wasserman Schultz has been inundated lately by negative press — most notably a spate of stories detailing an increasingly fractious relationship with the White House. Over the next several months she needs to change the narrative (and avoid doing anything that would make her subject to additional unwanted scrutiny).

Pelosi has singled out Israel as one of her favorites, and she could decide that the loyal ally and confidante could be a substitute to groom for bigger and better things in place of Van Hollen. In a sense, she has already begun the process, keeping him close and consistently seeking his input.

Sources say Israel might just want to have leadership’s ear, rather than be an elected leader, however. And if he ran, he might have to make a case for why his final term as DCCC chairman culminated in the party sinking to its lowest House minority in nearly a century.

And there are other, less obvious members waiting in the wings.

Rep. Ben Ray Luján of New Mexico is a few months into his first term leading the DCCC. Already well-liked within the caucus, he could garner even more goodwill if he delivers for the party in 2016, plus he’s part of the Congressional Hispanic Caucus.

Pelosi could encourage other, younger members to come into the fold, like fellow Californian Eric Swalwell and Massachusetts Rep. Joseph P. Kennedy III. Hoyer is mentoring Rep. Kyrsten Sinema of Arizona.

If Clyburn retires, the Congressional Black Caucus would want to field a candidate. Democratic sources list Reps. Terri A. Sewell of Alabama, Joyce Beatty of Ohio, Karen Bass of California, Cedric L. Richmond of Louisiana and even former CBC Chairman Emanuel Cleaver II of Missouri.

CBC member Donna Edwards of Maryland, who was recently named a co-chairwoman of the Democratic Steering and Policy Committee, is also someone with leadership ambitions, but she is expected to announce Tuesday that she’ll challenge Van Hollen in the primary for Mikulski’s Senate seat, with backing from the outside progressive community. Another African-American Democrat from Maryland, Oversight and Government Reform ranking member Elijah E. Cummings, is often mentioned as a future party leader, but is also looking at the Senate race.

Of course, any member who wants to be in leadership would have to prove he or she can raise the kind of money that has made Pelosi indispensable to the Democratic Party at large.

“Who’s the next person to hold that wallet?” asked a Democratic operative. “Who’re they going to trust?”

Related:

Van Hollen May Not Have Field to Himself

For Hoyer and McCarthy, the Floor Dance Is Getting Tense

Mikulski Legacy Is Beyond Longevity

Defiant Pelosi Stands Firmly on Left

Democrats Re-Elect Pelosi, Leadership Team for 114th Congress

Despite Drubbing, Pelosi and Hoyer Plan to Stick Around

The 114th: CQ Roll Call’s Guide to the New Congress

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