Now that Senator Bernie Sanders is effectively dropping out of the presidential race and endorsing Hillary Clinton, what's Donald Trump's best strategy for courting the former Sanders voters? I've already made the case that Trump can grab a very small but still significant number of Sanders' supporters simply because he is now the only "change" candidate still standing. And Trump is pulling no punches today, already expressing his "surprise" and accusing Sanders of selling out by joining the "rigged system."

That kind of sharp rhetoric makes sense because the one kind of Sanders voter Trump is most likely to have a shot at co-opting is the angry voter who believes both parties have sold out a large segment of the public for decades. These angrier voters will also tend to be a bit older than the average Sanders backer, who tended to be younger and more idealistic as opposed to being "angry."

Trump needs to avoid spending too much time trying to capture those younger and more idealistic voters who have shown absolutely no likelihood to come over to his side. But even a large number of Bernie backers moving over to Trump could end up meaning nothing at all if they shift in states that are already solidly in Clinton's or Trump's corner. That's where the geographic factor comes to play. Based on how Bernie Sanders fared in the primaries against Clinton, there are three states where Trump needs to concentrate his Sanders-conversion effort: Michigan, Ohio, and Pennsylvania.



Michigan may seem like a lost cause for any Republican. Barack Obama won the state by a relative landslide in 2008 with 57 percent of the vote and held on to most of that advantage with 54 percent in 2012 even against Michigan native Mitt Romney. But in 2000 and 2004, the state went to the Democrats by just 51 percent each time. And all of that is ancient history compared to Sanders' surprise win over Clinton in the Michigan primary this March. In that contest, Sanders didn't just clobber Clinton among his base of 18-29 year-olds; he also won a clear victory among 30-44 year-olds.

That group is the Trump campaign's sweet spot. This is a portion of the voters that is likely to favor Trump's attacks on NAFTA, TPP, and other trade deals. And in a union-heavy state like Michigan, union leaders have already acknowledged that Trump's message resonates with a lot of their rank and file despite the leadership's support for Clinton. Michigan hasn't gone for the Republicans in a presidential election since 1988, but the primaries proved the pollsters underestimated Clinton's weaknesses there.



Neighboring Ohio is another place Trump needs to concentrate his efforts on winning over any persuadable Sanders backers. The first reason is because Ohio is such a crucial state in every election, and the second reason is it's another strongly blue collar state where the Sanders voters were a little older on average than their peers in other states.

Clinton won the Ohio primary in mid-March, but Sanders grabbed a very solid 57 percent of the Democratic voters aged 30-39. He also won 57 percent of the male voters, grabbing a higher percentage of that gender than he did even in Michigan. 30-39 year-old males are another potential sweet spot for Trump, putting Ohio very much in play.



Pennsylvania is already turning out to be a state where Trump is showing some unexpected traction. Some polls have the Keystone State as a dead heat even though Democrats have won it in every presidential election since 1992. But like Michigan, Pennsylvania is a state where the Democrats' margin of victory was significantly reduced from 2008 to 2012.

And it's also a state where Sanders grabbed 57 percent of the 30-39 year-old voters. Trump has made his support for fracking, coal, and the entire fossil fuel industry very clear and the Pennsylvania economy's reliance on it has grown since President Obama took office.



It's important to remember that Trump doesn't even need to win over 30 percent of the Sanders primary voters in the above three states. 15 percent would be enough to make a serious difference and maybe as little as 10 percent would put him over the top in a state like Pennsylvania or Ohio. Of course, Trump isn't going to be vying for those votes in a vacuum.

The Democrats will likely not take them for granted, and so we can expect more Sanders-like proposals from Clinton like her plan for tuition-free college rolled out earlier this month. But if Clinton is forced to shore up that younger group of college-aged Sanders voters while Trump hits angry, working-age blue collar workers in the right states with his messaging, that's a game he can win.