Story highlights The task force is being led by Rep. Seth Moulton, a Marine Corps veteran

National security has made Democrats vulnerable in recent special elections

(CNN) Sensing an opening on national security issues, House Democrats are launching a new effort to counter President Donald Trump's foreign policy.

A trio of junior lawmakers with military and Pentagon experience will announce on Tuesday the formation of a new national security task force to push back on policies coming from congressional Republicans and the White House.

The task force is being led by Rep. Seth Moulton of Massachusetts, a Marine Corps Iraq veteran who has received some early 2020 presidential buzz.

It's both an outlet for out-of-power Democrats to showcase their ideas, as well as a recognition that Democrats continue to search for an effective message as they launch their midterm campaign and a wide-open field jostles for position heading into the 2020 presidential primary.

Before Trump's victory in November, many Democrats were sure they had the upper hand on national security in the 2016 campaign with former Secretary of State Hillary Clinton facing off against Trump.

Read More