White House officials said lawmakers were being pressured by outside groups that opposed the bill, through voter phone calls and television advertisements, with no pushback from several existing Trump organizations.
Trump son-in-law and adviser Jared Kushner, Priebus and chief strategist Steve Bannon told the website Thursday afternoon Walsh's move was "less shake-up and more rebooting of an outside effort that they believe failed them in their first, crucial legislative showdown".
However, many in the White House are hoping Walsh's departure fixes another one of the problems to plague the administration.
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Nunes is chair of the House intelligence panel, which is investigating Russian ties to the 2016 election and possible Trump campaign connections to Russia.
On Wednesday, in a sign of fresh urgency from Trump's allies, another pro-Trump nonprofit, Making America Great, sprang to life to help Trump - just days after the defeat of the Republican plan to repeal and replace the 2010 Affordable Care Act. The official said Walsh saw a need to better organize support for the White House's initiatives on the outside. Before her time at the RNC, she had worked on Fred Thompson and John McCain's 2008 presidential campaigns before moving onto the National Republican Senatorial Committee.
"She has been a tremendous asset to the President and we are confident she will be so in her new role as well", a White House official said.
Despite her low profile, Walsh has become a key player in the administration's inner circle and has grown close to the president in recent months. They brought with them one of the operatives initially slated to work at America First - Dave Bossie, a Mercer hand who had served as deputy campaign manager.