(CNN) A Democrat running for a US House seat in Pennsylvania offered praise for then-President-elect Donald Trump, called on Chicago Mayor Rahm Emanuel to resign and said progressives "are the least tolerant of anyone who disagrees with them" in a series of now-deleted tweets.

Northampton County District Attorney John Morganelli is running to replace retiring Republican Rep. Charlie Dent in what is now Pennsylvania's 7th District. Morganelli, who is a centrist Democrat running in a crowded field of six primary candidates, is backed by United Together, a group with reported ties with the bipartisan organization No Labels, and longtime Clinton associate Lanny Davis.

The race in Pennsylvania's 7th district pits the more conservative Morganelli against a slate of more liberal candidates, illustrating the intra-party ideological fights playing out nationwide among Democrats. Heading into Tuesday's primary, progressive groups are concerned that Morganelli, someone who once floated going to work for Trump's administration, could emerge as the party's nominee.

Morganelli has long been a hardliner on immigration, breaking with his party and advocating for a crackdown on illegal immigration. Since announcing his run in January, Morganelli has emphasized his efforts on several liberal policy priorities, including gun control, equal pay for women, alleviating student loan debt and increasing access to affordable health care.

Morganelli's candidacy has drawn the ire of progressive groups, with the pro-choice group EMILY's List and NextGen America, a group founded and funded by billionaire Tom Steyer, spending money to attack Morganelli.

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