HERSHEY, Pa. —  Republicans in Pennsylvania need to vote for their party's candidates because — though not officially — "Donald Trump is on the ticket this November," his eldest son said Friday night at a state GOP gathering.

In a 20-minute speech that was part a love letter to the state's Republicans who helped hand President Trump his unexpected 2016 victory, part an attack on Democrats, and occasionally an attempt at comedy, Donald Trump Jr. encouraged the party stalwarts to support the GOP candidates for governor, for Congress, and in state races.

"Each one of you, call your friends, get them out, talk to them about it. The only weakness that I see we could possibly have is that our side — we're fat and happy," Trump Jr. said at the state Republican Party's fall dinner. "You've got to recognize it: It can go away tomorrow." His biggest concern, he said, was "to get the nonvoter out."

Several independent polls have given Democrats comfortable leads in some key Pennsylvania races, including those for governor and Senate. But one of those polls, released late last month by Franklin and Marshall College, also found that a significant portion of voters, particularly Republicans and independents, remained undecided.

Republicans are hoping they can sway those voters as they attempt to maintain their grip on Congress and both chambers in the state legislature. Democrats are hoping they can increase their numbers to take control — or poise themselves for doing so in 2020.

Trump Jr., who attended the Hill School in Pottstown, credited the state with teaching him what "Rust Belt America was like." He spoke of hunting and fly fishing, and briefly pointed out a gunsmith, calling him "the most important man in this room."

He inserted jokes here and there. He said he didn't get a lot of sleep, and not because of his girlfriend, Kimberly Guilfoyle. The crowd laughed. "Get your mind out of the gutter," he said.

He spoke of the economy, North Korea, and Democrats' discussions about impeaching his father. "I don't know what their platform is: I say it's hate and B.S., but that's not really a platform," Trump Jr. said.

He received a standing ovation in the ballroom of the Hershey Lodge.

Democrats took note of his appearance. Before Trump Jr. took the stage, Nancy Patton Mills, chairwoman of the state Democratic Party, sent a fundraising email encouraging members of her party to make contributions or pledge to vote.