WILDWOOD — U.S. Rep. Jeff Van Drew was embraced with open arms Tuesday during President Donald Trump’s rally at the Jersey Shore, just one month after the longtime Democrat defected to the GOP.

“Jeff had the guts to defy the left-wing fanatics in his own party,” Trump said at the Wildwoods Convention Center, adding that “it didn’t take much” for Van Drew to switch parties.

Tuesday’s rally cemented Van Drew’s new status as a Republican, and marked the most high-profile effort to date by the national party to boost his reelection chances in 2020. Trump invited Van Drew to share the stage, showering the longtime moderate Democrat with praise and highlighting his conservative-leaning positions.

“He supports lower taxes; not bad," Trump said. “He loves our military, he loves our vets and police. ... He loves your Second Amendment, which is under siege by the Democrats.”

Van Drew shook New Jersey politics in December when, in rapid succession, he voted against Trump’s impeachment, switched parties, and pledged his “undying support" to Trump. Democrats were furious at the betrayal, while local Republicans were skeptical of his conservative bona fides.

» READ MORE: Democrats are furious at Jeff Van Drew. But beating him won’t be easy.

At the rally, Van Drew tried to remove any doubt about his loyalty, taking to the lectern to fully embrace his new political home — and Trump.

“When I was in the White House with the president, he asked how he could help me," Van Drew said. “I asked if he could come down to South Jersey to have a rally. Without even hesitating, our president said yes, and he is here. A man who kept his word to ensure that the eyes of the world are on South Jersey.”

Hours before Trump took to the stage, prominent New Jersey Republicans — Van Drew’s political foes for years — also toed the line with shows of support for the Democrat-turned-Republican, reflecting the strength of Trump’s support in conservative bastions of South Jersey.

“Jeff is going to win in November,” said David Richter, a Republican who had been running before Van Drew switched parties and vowed to continue the campaign against him, but announced Monday that he would run instead in a neighboring district represented by Democrat Andy Kim. “He stood with President Trump and voted against this impeachment farce. He knows how to deliver for South Jersey. He’s tough, he gets the job done.”

Just weeks earlier, Richter had dismissed Van Drew as “fake.”

"I don’t think they’re going to put their support behind a lifelong Democrat,” Richter said of voters in December. “I wish more people would leave the Democratic Party. But if you do it opportunistically, [it] just smacks of being... very fake.”

» READ MORE: ‘I will not vote’ for Trump, Jeff Van Drew vowed in a voicemail. Then he pledged ‘undying support’ for the president

The rally also offered Trump and Van Drew a break from what has otherwise been a tumultuous time for the president and his new ally, both of whom face challenging reelections in November.

Trump’s impeachment trial is entering a potentially dangerous phase, with Senate Majority Leader Mitch McConnell signaling to colleagues Tuesday that he doesn’t have the votes to block new witnesses from testifying.

And just days before the rally, the strength of Van Drew’s newfound loyalty to the president was called into question with the emergence of a voicemail he left for a voter. “I haven’t voted for him, I didn’t support him, I will not vote for him," Van Drew said of Trump in the Nov. 30 message, just three weeks before he defected to the GOP and pledged the president his “undying support."

While Van Drew played a starring role in Trump’s rally, his Democratic challengers said his sudden political reversal was nothing more than opportunism. In early December, Van Drew learned from an internal campaign poll just how much his stance on impeachment had harmed his prospects in a Democratic primary. Days later, he was in the White House finalizing plans to become a Republican.

“He’ll say and do anything to get reelected,” said Brigid Callahan Harrison, a Democrat angling for Van Drew’s seat. “It isn’t this was an evolution in his politics, it’s clear it’s about his own reelection chances.”

Since switching parties, a number of prominent local Democrats have decided to run for his seat, and many of them used Tuesday as an opportunity to attack Van Drew in front of a wider audience.

Amy Kennedy, a candidate in the Democratic primary and the wife of former Rep. Patrick Kennedy, ran an ad during Fox and Friends, Trump’s favorite cable news talk show. It showed footage of Van Drew pledging his “undying support” to Trump in the Oval Office before featuring Kennedy herself saying: "I’m a lifelong Democrat. That’s who I am and it’s who I’ve always been.”

And while Van Drew’s reelection campaign will be one of the most closely watched House races in the country, it remains to be seen if Trump’s support will ultimately be enough to deliver a victory.

The district — which stretches from the Philadelphia suburbs in Gloucester County south to Cape May, and from north of Atlantic City into Burlington County — is a battleground: Trump won it by five points in 2016, while President Barack Obama got 53% of the vote each time he ran.