Sen. Elizabeth Warren Being Vetted for Hillary Clinton Vice President Pick The Massachusetts senator has been campaigning with Clinton.

 -- Sen. Elizabeth Warren is being formally vetted as a possible vice presidential pick for Hillary Clinton, according to a source familiar with the process.

Warren is not the only contender being formally vetted at this point.

The Massachusetts senator, considered a leader among progressives, campaigned with Clinton today for the first time since endorsing her earlier this month.

If Clinton picks Warren as her vice president, Clinton would make history again. Two women have never headlined a major party’s presidential ticket.

Throughout the primaries, Clinton has had trouble garnering the votes of independents and young voters. If she chooses Warren, that could be viewed as an effort to win over Bernie Sanders' supporters because, like Sanders, Warren rails against Wall Street and speaks often of the plight of America’s middle class.

The two met at Clinton’s Washington, D.C., home earlier this month to discuss how they can work together to stop Republican presumptive nominee Donald Trump.

Warren has been a vocal opponent of Trump in recent weeks, openly engaging in debates with the him over social media.

She ignited a feud with Trump in May, calling him out for “racism, sexism and xenophobia,” arguing that there was more support for Trump among members of the KKK than among Republican Party leaders.