While the full caucus typically backs the Steering Committee’s pick, an upset has occurred as recently as 2014.

Lawmakers and aides watching the race expect it will be decided on a second round of voting for DeLauro and Wasserman Schultz, with allies of the Florida Democrat hopeful she can eke out a win with the help of Kaptur supporters forced to throw their support behind another candidate. The Ohio Democrat is not expected to secure enough support on the first ballot.

Kaptur, 74, the most senior Democrat on the spending panel and the longest-serving woman in Congress, has won support from many members of the Congressional Black Caucus — a powerful bloc that typically respects seniority in leadership elections. Supporters of Wasserman Schultz say she could win if she can secure even some of those votes.

DeLauro’s supporters, however, are confident that the close ally of Speaker Nancy Pelosi and long-time champion of the public health and education communities will be confirmed as chair.

Pelosi typically doesn't get involved in steering races after she publicly backed Rep. Anna Eshoo (D-Calif.) in 2014, who won the steering panel’s nod to become the top Democrat on the Energy and Commerce Committee in 2014, only to lose the spot in a stunning caucus-wide vote. The caucus instead chose Rep. Frank Pallone (D-N.J.), who went on to become Energy and Commerce chair.

DeLauro — the second-most senior contender for the gavel who controls the largest chunk of nondefense spending as the head of the Labor-HHS-Education subcommittee — has long been expected to lead the appropriations panel and has a reputation for working with senior Republican appropriators like Rep. Tom Cole (R-Okla.).

DeLauro, 77, is a “work horse” and a “force of nature,” said Rep. Linda Sánchez (D-Calif.), who’s pushing her colleagues to vote for the Connecticut Democrat, in an interview last month. “Her appeal is that she has integrity, that she has wisdom, that she’s such a hard worker and a strong fighter for the issues that she cares about.“

Wasserman Schultz, who chairs the Military Construction-VA spending panel, has been expected to pick up support from freshmen, moderates and some members of the CBC. Supporters point to her robust fundraising for Democrats — particularly for vulnerable members that will be crucial to keeping the House majority in 2022.

Some Democrats said a disappointing Election Day that cost the party more than a half-dozen House seats underscores the need for change, including a more moderate candidate that could bring generational diversity to the leadership ranks.

“I think that in the aftermath of the election, it makes clear that the old ways of doing things just aren’t going to work anymore,” Rep. Stephanie Murphy (D-Fla.), a co-chair of the moderate Blue Dog Democrats who supports Wasserman Schultz, said last month.

The three Democrats are vying to succeed retiring Chair Nita Lowey (D-N.Y.), the first woman ever to lead the spending panel. All three have vowed to make the appropriations process more transparent and accessible to members, while supporting the return of earmarked spending to help Democrats secure cash for pet projects at home.

Heather Caygle contributed to this report.