Hillary Clinton and Bernie Sanders are fighting for the title of 'progressive'

After nearly losing to Bernie Sanders in the Iowa caucuses earlier this week, Hillary Clinton has turned her attention to the Vermont senator ahead of another showdown next week in the New Hampshire Primary.

The pair of Democratic presidential candidates are now battling it out over who is more progressive in an attempt to woo voters before Tuesday's first-in-the-nation primary vote, where Mr. Sanders has a sustained lead in the polls.

Sen. Sanders readily identifies as a progressive candidate, campaigning on reining in Wall Street and making college tuition free at public universities. Former Secretary of State Clinton identifies as a more moderate candidate, willing to work across the aisle. But she bristled after her in-party rival blasted her for claiming to have a progressive record.

The senator took to Twitter Wednesday to call out Mrs. Clinton for not being progressive enough in her politics.

Mrs. Clinton, for her part, fired back at Sen. Sanders, pointing to times his record could be considered less-than-progressive.

But what exactly is considered progressive in American politics? For some, it's another word for liberal, used by politicians who may feel the word "liberal" has become overly politicized. In a Huffington Post article written in 2011, David Sirota says, "It seems to me that traditional 'liberals' in our current parlance are those who focus on using taxpayer money to help better society. A 'progressive' are those who focus on using government power to make large insititutions play by a set of rules."

The Heritage Foundation says that liberalism is "the use of government to grant benefits and advantages in order to give everyon the ability to achieve a certain standard of living and reduce inequalities." The organization defines progressivism as a step beyond liberalism because of "heavy regulation and other controls."

In the end, at the polls in New Hampshire and beyond, it's doubtful that voters will be making their decisions based on who has a better definition of progressivism, something Mrs. Clinton noted on Twitter.

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