The Obama White House has left the sidelines and jumped in with both feet as Massachusetts lawmakers debate whether to change current law and appoint an interim U.S. Senator to replace the deceased Edward M. Kennedy.

FOX News has learned Senior White House adviser David Axelrod called the president of the Massachusetts Senate on Monday to lobby for the law change to fill Kennedy's Senate seat until the Jan. 19 special election is held.

Axelrod called Therese Murray to discuss the matter, Deputy White House Press Secretary Bill Burton confirmed to FOX late Tuesday.

Burton said Axelrod was "checking in" with Murray, but Democratic sources say the call was designed to underscore White House interest in seeing Massachusetts law changed and an interim Senator appointed as crunch-time approaches in the health care debate.

In addition to his closeness to Obama, Axelrod also has deep ties to Massachusetts Gov. Deval Patrick. The governor wants the Legislature to give him power to appoint Kennedy's successor. Axelrod's leverage may prove useful to Patrick in this regard.

The Obama White House wants and needs as many Democrats as it can get for health care. An interim appointment would raise its number of Democrats available on a daily basis to 59. Sen. Robert Byrd of West Virginia is ill and rarely present for Senate debate and votes.

Two names continue to surface as Kennedy's replacement: former Kennedy aide and former DNC Chairman Paul Kirk, and former Massachusetts Governor and 1988 Democratic presidential nominee Michael Dukakis.

Kirk is still thought to have the inside track as a keeper of the Kennedy flame and party loyalist through-and-through. Even so, Dukakis has been lobbying lawmakers in the legislature for the opportunity - albeit it brief - to wrestle with one of the biggest domestic issues of the Obama presidency. The constituency for Kirk appears to include the vast majority of Kennedy family members as well as Washington-based Democrats. Dukakis's constituency appears mostly of him and an assortment of aides and advisers in Massachusetts who worked on his gubernatorial or presidential campaign staff.

Senior Senate Democratic leaders have, so far, declined to publicly state a preference.

The Massachusetts House is due to vote on the interim-appointment bill on Thursday and the Senate, led by Murray, is expected to follow suit. No dates for Senate action have been firmly established.