By Eric Stock

BLOOMINGTON – Bernie Sanders has been closing in on Hillary Clinton’s lead in delegates in the Democratic presidential race by winning eight of the last nine contests, but a political expert said Sanders’ biggest obstacle remains his own party.

Retired politics and government professor from Illinois State University Bob Bradley told WJBC’s Scott Laughlin the so-called superdelegates, many of whom are elected officials, continue to support Clinton by a wide margin.

PODCAST: Listen to Scott’s  interview with Bradley on WJBC.

“Part of the reason for that is the superdelegates for the most part do not want Bernie Sanders and it’s primarily because of how Bernie Sanders has treated the Democratic Party in Congress,” Bradley said.

Bradley said Sanders’ role as an independent in Congress’ has alienated him from the party base though Bradley adds the Democrats would have a public relations problem if the primary voters select a candidate and the superdelegates essentially overturn that vote.

The two frontrunners in the presidential primaries have lower favorability ratings than their challengers and Bradley said these low ratings for nearly all the contenders in unprecedented.

“I was just thinking back as to whether you’ve had the majority of the people at this stage having 50 percent or worse unfavorable rankings and I don’t (recall),” Bradley said.

Republicans Donald Trump and Ted Cruz have favorability ratings at 26 percent according to an Associated Press GfK poll.

Sanders had the highest favorability ratings among all the candidates at 48 percent. John Kasich leads about the Republicans at 34 percent.

Eric Stock can be reached at [email protected].