It is conventional political wisdom that President Trump stands his best chance in 2020 if Democrats nominate a progressive candidate on the far left such as Bernie Sanders or Elizabeth Warren. That is half right. I have witnessed both of these candidates up close as a former chairman of the Vermont Republican Party when Sanders rose from the backbench of the House to the Senate, and as campaign manager for the Senate reelection of Scott Brown against upstart Warren in Massachusetts. It has given me some insight into both their strengths and weaknesses as candidates.

While Sanders may be a socialist, his populist brand of rabble rousing mirrors Trump, and could cut into the new Republican blue collar base. Warren, on the other hand, is a traditional liberal who poses as a populist. Working class voters recognize the difference between the sincerity of Sanders and the sanctimony of Warren. To better understand this political dynamic, compare two instructive elections in locations that have little in common, one in tiny Essex County in the most rural northeast corner of Vermont and another in the only New England metropolis of Boston.

Essex County is the most Republican part of what was once the most Republican state in the nation. Today it is the lone Republican holdout among the 14 counties in Vermont. In 2016, it was the red dot in the blue sea of the state, going for Trump by 18 points. Flashback to 2006 when Sanders ran for the open Senate seat in the only serious contest he had faced since 1994 when he was a member of the House and socialism was still a dirty word. Sanders cruised to victory and won Essex County with 59 percent of the vote, even as those same people had overwhelmingly backed the reelection of their Republican Governor James Douglas.

Vermont is not up for grabs in 2020 or anytime soon. But these same white rural working class voters are scattered throughout Pennsylvania, Wisconsin, and Michigan. They delivered Trump his narrow win in 2016. Fast forward six years to Boston and the 2012 election when Warren rode the coattails of President Obama to the Senate. Republican presidential candidate Mitt Romney, the former Massachusetts governor and party standard bearer, lost Boston proper without cracking 20 percent. Warren won big there as well but trailed the showing of Obama by five points.

Why? Because in places like gritty South Boston, many working class voters rejected her. Like in Essex County in Vermont, these are Trump voters and could also be Sanders voters. But they are not buying what Warren is selling. As Warren marched in the South Boston Saint Patrick Day parade thar year, one man on the curb mimicked her often repeated refrain about the "hammered" state of the middle class with a disdainful twist as only a Bostonian could and said, "Hey Warren, this is the middle class getting hammered," as he downed the final swig of his Bud Light.

So these street smart voters can sense a phony when they see one, and Warren is a fraud of the first order. Whether it is the uproar over her wine cave hypocrisy, her false claim of being Native American to gain a leg up in her teaching career, or her faux outrage at big corporations she used to collect huge paychecks from, she will say or do anything to get ahead.

Like him or not, Sanders is anything but fake. He has been singing off the same song sheet for a half century. You will not find any big corporations on his resume. His disdain for millionaires and billionaires is as fervent as ever, even as he has become one. He does not shrink from his ideas out of political expediency. He believes what he says, as wild as it may sound.

With the Cold War in the rear view mirror, many culturally conservative blue collar types can look past his ideological extremism to see someone promising to shake up the status quo bigly. That is the same quality they saw in Trump, who in 2016 won Pennsylvania, Wisconsin, and Michigan by less than 78,000 votes. In 2020, he cannot afford any attrition. If the past is a prologue, Sanders can take some of those critical votes. Warren has no such track record. That is why Trump should be rooting for Warren.

James Barnett is a Republican strategist and founding partner of the public affairs firm Battleground Strategies. He served as a campaign manager for Maryland Governor Larry Hogan and Massachusetts Senator Scott Brown.