Rep. Tammy Duckworth has not officially announced her 2016 intentions, but the behind-the-scenes jockeying to replace the two-term congresswoman in her suburban Chicago House district should she run for Senate has already begun in earnest.  

Three Democrats are actively making calls to build support and gauge interest in their candidacies in the 8th District, according to Democratic operatives in the state. It’s a surefire sign Duckworth is moving toward a challenge to Republican Sen. Mark S. Kirk.  

“She is speaking to her House colleagues about personal matters — raising a family and doing the job,” said one Illinois Democratic operative. “Indications are strong that she’s about to get into this.”  

Duckworth’s office did not return request for comment on her plans. But she will meet with her top political donors on Monday in the state, and has encouraged donations for a possible Senate bid, according to the Chicago Sun Times.  

Needing to net five seats to take control of the Senate, the Democratic Senatorial Campaign Committee will heavily target Kirk in 2016. His race is rated a Tossup  by the Rothenberg & Gonzales Political Report/Roll Call.  

National Democrats hope Duckworth will jump in. They say her experience as a disabled veteran, as well as her geographical base in the Chicago suburbs, gives her the kind of profile the party needs to oust Kirk after a single term.  

State Sens. Tom Cullerton and Mike Noland, as well as former Illinois Deputy Treasurer Raja Krishnamoorthi, are considering bids for Duckworth’s seat, located west of Chicago.  

Krishnamoorthi lost a 2012 primary challenge against Duckworth — when Democrats were looking to oust then-Rep. Joe Walsh. Duckworth had support from a number of Illinois Democrats, most notably Sen. Richard J. Durbin. Yet Krishnamoorthi stayed in the primary, raising more than $1 million.  

Cullerton, who hails from Villa Park, is from a well-known political family in Illinois. His cousin, John Cullerton, is the state Senate president — a powerful position in Springfield. His other cousin, Timothy Cullerton, is from a long line of Chicago aldermen. Cullerton, an Army veteran, has strong ties to labor — a powerful influencer in Illinois politics. He won his competitively drawn state Senate seat in 2012 with union support. Noland represents a state Senate district that encompasses Elgin, Ill., located in the far western portion of the district. A Marine veteran, Noland has served in the state Senate since 2007.  

If Duckworth does run for Senate, Democrats would be favored to keep her House seat. President Barack Obama carried it in 2012 by a 17-point margin, making a Democratic candidate a strong favorite here in 2016.  

Related:

Tammy Duckworth: I’m ‘Taking a Real Serious Look’ at Senate Run


Kirk Starts 2016 as an Underdog


First Senate Race Ratings Revealed


Mark Kirk: ‘No Frickin’ Way Am I Retiring’


Kirk Vs. Duckworth for Senate in 2016?


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


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