It's the "issues" stupid.

The reference is to an effort to keep the Clinton campaign
on message, wikilink.

Keeping a political campaign "on message" does not mean keeping the campaign on issues; in fact it means quite the opposite. At best, it means a single issue; not about all of the issues.

There is almost no debate on issues. Instead, we hear candidates like Brian Colón saying things, link, like;

he is "... going to fight to stop Republicans who are hurting public schools".

Does that sound like a debate of issues? or does it sound like a campaign staying on message; Republicans are bad, Republicans are bad, Republicans are bad, ...

It is a campaign that plays on the lack of intelligence and sophistication of many voters.

They would be offended, if only they had the intelligence and sophistication to understand what Colón and others are doing to them.