Story highlights Hillary Clinton's supporters on Capitol Hill warn that Bernie Sanders will face increased scrutiny after New Hampshire

"I think when someone starts to look into Bernie Sanders' record, sure things change," said Senator Dianne Feinstein of California

(CNN) Hillary Clinton's supporters on Capitol Hill are bracing for a win by Bernie Sanders in the New Hampshire primary Tuesday, but warn the Vermont senator will face increased scrutiny in the next phase of the campaign.

"I think when someone starts to look into Bernie Sanders' record, sure, things change. I think that hasn't happened," Sen. Dianne Feinstein of California, a Clinton backer, told CNN. "Look at the seven taxes he would raise to do single payer (health coverage). There are a lot of technical things that show a person's record that just haven't come out yet and I think later on there is room for that."

Feinstein and other Clinton congressional surrogates have a long list of Sanders' controversial but overlooked policy items they plan to highlight in the weeks ahead to demonstrate the self-described democratic socialist's record is too liberal to win the White House, a Democratic aide told CNN.

Multiple congressional Democrats backing Clinton admit that Sanders' near win in Iowa, and rise in the national polls took them somewhat by surprise, but instead of showing signs of panic they seem resigned to a longer two person nomination fight. They believe that younger voters attracted to Sanders' anti-Wall Street message will ultimately rally behind Clinton's candidacy because Republican candidates aren't emphasizing the same commitments to education and health care that Democrats are discussing on the campaign trail.

The Clinton campaign has conducted regular calls with supporters on Capitol Hill, has briefed members on longer term operations in states voting later in February and March, and is tapping into help from surrogates in key states.

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