As Democrats gathered for the final night of their national convention in Charlotte on Thursday, the first family of the Democratic Party took another step toward returning to Congress.

Joe Kennedy III easily won his congressional primary Thursday in Massachusetts.

The 31-year-old son of former congressman Joe Kennedy II and grandson of Robert F. Kennedy had a huge financial advantage over two lesser-known opponents and easily grabbed more than 90 percent of the vote. He is a heavy favorite to succeed retiring Rep. Barney Frank (D-Mass.) in a strongly Democratic district.

The Kennedys have held no seats in Congress --  for the first time in decades -- since Sen. Ted Kennedy (D-Mass.) died in 2009 and Rep. Patrick Kennedy (D-R.I.) retired in 2010.

Elsewhere in Massachusetts, both Reps. Richard Neal (D) and Bill Keating (D) survived in redrawn districts against significant opposition. Keating, a freshman, had the closer call, taking about 60 percent of the vote against Bristol County District Attorney Sam Sutter.

In the state's Senate race, Elizabeth Warren (D) had already won her party's nomination at the state party convention earlier this year and faced no opposition. She is running hard against Sen. Scott Brown (R-Mass.) in a top general-election race and addressed the convention on Wednesday.